8 International School of Organometallic Chemistry

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8 International School of Organometallic Chemistry
8th International School of Organometallic Chemistry
SUMMER SCHOOL
Camerino, Italy
27-31 August 2011
http://portal.unicam.it/isoc/
University of Camerino
School of Pharmacy
School of Science and Technology
Interdivisional Group of Organometallic Chemistry
Tailored Organometallic Complexes With Improved Functions
INTRODUCTION
“TAILORED ORGANOMETALLIC COMPLEXES WITH IMPROVED FUNCTIONS”
Almost all branches of chemistry and material science now interface with Organometallic Chemistry. Organometallics are used
extensively in the synthesis of useful compounds on both large and small scales. Industrial processes involving plastics, polymers,
electronic materials, and pharmaceuticals all depend on advancements in organometallic chemistry. Many catalytic and non-catalytic
stereoselective processes that are key steps in creative and non-conventional synthesis of complex molecules have gained significant
advantage from organometallic chemistry.
The ISOC series is the most important school on organometallic chemistry at the European level, organized under the auspices of
EuCheMS (the European Association for Chemical and Molecular Sciences) and the interdivisional group of organometallic
chemistry of the Italian Chemical Society with the aim of encouraging the presence of young researchers and Ph.D. students both
from University and Industry, including those not directly involved in organometallic research projects, in order to bring together
young researchers and distinguished European scientists as a contribution to the important goal of increasing the transfer of
knowledge at a high level between different European countries and different generations of Scientists. The major objective of the
ISOC 2011 is to promote synergy in organometallic research. The number of participants will be limited to around 100 in order to
facilitate maximum interaction among the participants and between them and the lecturers.
The 8th edition of ISOC (ISOC 2011) will focus on the relevance of basic research in organometallics as a fundamental tool for
the discovery of new applications. The development of advanced methodologies based on the peculiar properties of organometallic
compounds may lead to important changes in the approach of organometallic chemists to the field. A full roster of scientifically
distinguished speakers will present their reading keys. In fact, fundamental studies on the mechanistic and structural aspects, as well
as new experimental methods and investigation techniques, support the use of organometallic compounds in different application
areas including Organometallic Catalysis, Bioorganometallic Chemistry in Biology and Medicine, Green Chemistry (energy and
sustainable development), Industrial chemistry and Polymers production, Metal-mediated organic synthesis and Activation of small
molecules.
TIMETABLE
Saturday
15,30
16,00
17,30
18,00
27 August
Opening Session
Prof. M. Bochmann
Coffee break
A. Llobet
Sunday
9,00
10,30
11,00
28 August
Prof. A. Abbotto
Coffee break
Prof. L. Sun
14,30
16,00
16,30
18,30
Prof. E. Clot
Coffee break
Flash Presentations
Prof. P. Braunstein
Poster session
20,00
20,30
Visit to Civic Museum Welcome Dinner
Monday
8,30
10,00
11,30
11,45
29 August
Prof. M. P. Coogan
Prof. I. Marek
Coffee break
Prof. R. Réau
15,00
20,00
Excursion
Social dinner
Tuesday
9,30
11,00
11,30
30 August
Prof. N. Krause
Coffee break
Prof T. R. Ward
15,00
16,30
17,00
18,00
Prof. J. Lacour
Coffee break
Flash Presentations
Poster Session
Wednesday
8,30
10,00
10,15
11,45
31 August
Prof A. Albinati
Coffee break
Prof. P. Andersson
Flash Presentations
12,45
Prizes and Closing
Ceremony
PROGRAMME
Saturday, 27 August:
15,30: Opening Session
16,00: Prof. Manfred Bochmann “Introduction to Olefin Polymerization Catalysis: From Black-Box
Systems to Well-Defined High-Activity Catalysts”
17,30: Coffee break
18,00: Antoni Llobet “Molecular catalysts that oxidize water to dioxyen”
Sunday, 28 August:
9,00: Prof. Alessandro Abbotto “Organometallic complexes for a new generation solar energy”
10,30: Coffee break
11,00: Prof. Licheng Sun “Solar Energy Conversion by Molecular Catalysts Inspired by the Active Sites
of Photosystem II and FeFe-Hydrogenases”
14,30: Prof. Eric Clot “18-electron rule: myth or reality? A Natural Bond Orbital perspective”
16,00: Coffee break
16,30: Flash Presentations and Poster session
18,30: Prof. Pierre Braunstein “Metal-Metal Bonds and d10-d10 Interactions”
20,00: Visit to Civic Museum
20,30: Welcome Dinner
Monday, 29 August:
8,30:
10,00:
11,30:
11,45:
15,00:
20,00:
Prof. Michael P. Coogan “Organometallic Complexes of Transition Metals in Luminescent Cell
Imaging Applications”
Prof. Ilan Marek “New Approaches to the Enantioselective Synthesis of all-Carbon Quaternary
Stereogenic Centers in Acyclic System”
Coffee break
Prof. Regis Réau “Organometallic Derivatives as Smart Materials for Optoelectronics”
Excursion
Social dinner
Tuesday, 30 August:
9,30:
11,00:
11,30:
15,00:
16,30:
17,00:
18,00:
Prof. Norbert Krause “Combined Coinage Metal Catalysis for the Synthesis of Bioactive
Molecules”
Coffee break
Prof Thomas R. Ward “Merging the Best of Both Worlds: Artificial Metalloenzymes”
Prof. Jérôme Lacour “Investigations in Asymmetric Synthesis and Catalysis”
Coffee break
Flash Presentations
Poster session
Wednesday, 31 August:
8,30:
10,00:
10,15:
11,45:
12,45:
Prof Alberto Albinati “X-ray diffraction and neutron scattering: powerful tools for studying
structures and reactivity in organometallics compounds”
Coffee break
Prof. Pher Andersson “Development of Iridium-Catalyzed Asymmetric Hydrogenation: New
Catalysts, New Substrate Scope”
Flash Presentations
Prizes and Closing Ceremony
ORGANIZING COMMITTEE
Augusto CINGOLANI
Honorary President of ISOC
Claudio PETTINARI
Fabio MARCHETTI
Chair
Co-chair
Riccardo PETTINARI
Corrado DI NICOLA
Roberto BALLINI
Marino PETRINI
Adriano PIZZABIOCCA
Enrico MARCANTONI
Advisory Board
Scientific Committee
Claudio BIANCHINI (ICCOM-CNR Firenze, Italy)
Marino BASATO (President of GICO)
Pierre BRAUNSTEIN (University of Strasbourg, France)
Maurizio PERUZZINI (President of Inorg. Chem. Division – SCI)
Luigi BUSETTO (University of Bologna, Italy)
Raffaele RICCIO (President of Org. Chem. Division – SCI)
Sandro CACCHI (University of Roma, Italy)
Augusto CINGOLANI (Honorary President of ISOC)
Ernesto CARMONA (University of Sevilla, Spain)
Claudio PETTINARI (Chair)
Augusto CINGOLANI (University of Camerino, Italy)
Francesco SANNICOLO’ (Past President of GICO)
Kees ELSEVIER (University of Amsterdam, Netherlands)
Luigi BUSETTO (EuCheMS Delegate)
Josè GIMENO (University of Oviedo, Spain)
Antonella DALLA CORT
Roberto GOBETTO (University of Torino, Italy)
Silvia BORDONI
Stefano MAIORANA (University of Milano, Italy)
Emanuela LICANDRO
Giovanni NATILE (University of Bari, Italy)
Alceo MACCHIONI
Luis A. ORO (University of Zaragoza, Spain)
Enrico MARCANTONI
Robin N. PERUTZ (University of York, UK)
Alessandro MORDINI
Maurizio PERUZZINI (ICCOM-CNR, Firenze, Italy)
Fabio RAGAINI (GICO)
Claudio PETTINARI (University of Camerino, Italy)
Giovanni POLI (P. M. Curie University, Paris, France)
Rinaldo POLI (LCC, CNRS, Toulouse, France)
Armando POMBEIRO (IST, Lisboa, Portugal)
Mats TILSET (University of Oslo, Norway)
Valerio ZANOTTI (University of Bologna, Italy)
SPEAKERS
Ilan Marek
I.I.T., Haifa, Israel
New Approaches to the Enantioselective Synthesis of all-Carbon Quaternary Stereogenic Centers in Acyclic System
Norbert Krause
University of Dortmund, Germany
Combined Coinage Metal Catalysis for the Synthesis of Bioactive Molecules
Jérôme Lacour
University of Geneve, Switzerland
Investigations in Asymmetric Synthesis and Catalysis
Thomas R. Ward
University of Basel, Switzerland
Merging the Best of Both Worlds: Artificial Metalloenzymes
Regis Réau
University of Rennes, France
Organometallic Derivatives as Smart Materials for Optoelectronics
Antoni Llobet
University of Terragona, Spain
Molecular catalysts that oxidize water to dioxyen
Manfred Bochmann
University of East Anglia, United Kingdom
Introduction to Olefin Polymerization Catalysis: From Black-Box Systems to Well-Defined High-Activity Catalysts
SPEAKERS
Michael P. Coogan
University of Cardiff, United Kingdom
Organometallic Complexes of Transition Metals in Luminescent Cell Imaging Applications
Eric Clot
University of Montpellier, France
18-electron rule: myth or reality? A Natural Bond Orbital perspective
Alessandro Abbotto
University of Milano-Bicocca, Italy
Organometallic complexes for a new generation solar energy
Alberto Albinati University of Milano, Italy
X-ray diffraction and neutron scattering: powerful tools for studying structures and reactivity in organometallics
Pierre Braunstein
University of Strasbourg, France
10
Metal-Metal Bonds and d -d10 Interactions
Licheng Sun
Royal Institute of Technology, Stockholm, Sweden
Solar Energy Conversion by Molecular Catalysts Inspired by the Active Sites of Photosystem II and FeFeHydrogenases
Pher Andersson
University Uppsala, Sweden
Development of Iridium-Catalyzed Asymmetric Hydrogenation: New Catalysts, New Substrate Scope
LECTURES
Organometallic complexes for a new generation solar energy
X-ray Diffraction and Neutron Scattering: Powerful Tools for Studying the Structure and
Reactivity of Organometallic Compounds.
Alessandro Abbotto
Alberto Albinati
Department of Materials Science and Milano-Bicocca Solar Energy Research Center - MIB-Solar, University of Milano-Bicocca, Via Cozzi 53,
I-20125, Milano, Italy; [email protected] unimib.it
Department of Structural Chemistry, University of Milan, 20133 Milan, Italy
Global energy needs are predicted to growth by a factor of three to four in the next few decades, making the
[email protected]
exploitation of clean and renewable sources a priority of our modern society. The Sun is by far the most abundant clean and
cheap source of energy to keep pace with the growing energy demand if one considers that the solar power striking the
planet is four orders of magnitude larger than world power consumption. Thus, capture of sunlight has attracted an
The use of X-ray diffraction for elucidating the molecular structures of coordination compounds is now so
widespread, due to the improvements in hardware and software, to be considered almost “routine”.
increasing interest in the academic and industrial community. Amongst new generation thin film photovoltaic (PV)
After a very brief introduction to diffraction I will give a few examples on how X-ray data can give an important
technologies, dye-sensitized solar cells (DSC) own a great potential in terms of low cost-performance trade-off, future
contribution to the study of weak interactions, such as non-classical M···HX hydrogen bonds and dipolar interactions in
development, and scale up to market.
ionic complexes that may dictate the overall geometry and influence the reactivity. Using as example cationic Pd(II)
Starting from an introduction to solar energy and a brief description to photovoltaics and operational principles of
complexes and complexes based on the “Ru(cp*)(η6-arene)” moiety I will show how the location of the counter-ions, as
DSCs, this lecture will review the most important and recent advances on tailored organometallic complexes as components
revealed by X-ray diffraction, parallels the behaviour in solution as shown by NMR PGSE measurements; moreover the
(photosensitizers and electrolytes) of DSCs, focusing on the structural, optical and energetic factors responsible of the
short packing distances are consistent with those from NOE experiments. The existence of this ion pairing may, in turn,
ultimate performances in the device.
[1]
The largest section will be devoted to the description of organometallic sensitizers,
explain differences in the reactivity pattern.
including Ru(II) polypyridyl complexes, substituted π-conjugated complexes, cyclometalated complexes, porphyrines and
One should note that, while in the above mentioned cases the accuracy in the determination of the H atoms positions
phtalocyanines. Finally, we will address main open issues, roadmaps to future development, and perspectives. In this
is not critical and X-ray diffraction may give all the necessary information, the unambiguous proof of the existence of weak
context, we will also present our recent activity on new organometallic (polypyridine and cyclometalated complexes) DSC
M…HX interactions requires a far greater accuracy in the H atoms location that can only be obtained by neutron
photosensitizers, highlighting superior optical and photovoltaic properties.
[2]
diffraction, as shown in the study of the complex trans-[PtCl2(NH3)(N-glycine)].H2O.
Indeed neutrons are a wonderful tool to probe the structure and dynamics of molecules due to their unique properties.
For example, a series of accurate single crystal neutron diffraction have allowed the determination of the H-H separation,
as a function of the metal and the ligands, neatly spanning the reaction pathway of the oxidative addition of dihydrogen to a
metal centre.
However, a satisfactory description of the bonding in hydrides may not be complete without the detailed knowledge
of their dynamics. Inelastic Neutron Scattering (INS) studies have been instrumental in providing detailed information on
the M-H2 interaction, in particular by means of rotational tunnelling spectroscopy. The INS technique has also been used
to study the dynamics of the (H2)/H exchange. As an example I will discuss this exchange in the octahedral complexes:
trans-(PiPr3)2IrX(H)2(H2) (X = Cl, Br, I) and the unambiguous experimental observation of the associated activation
energy.
References
[1]
Some recent reviews are: Abbotto, A.; Manfredi, N. Dalton Trans. 2011, in press; Hagfeldt, A.; Boschloo, G.; Sun, L.; Kloo, L.;
Pettersson, H. Chem. Rev. 2010, 110, 6595; Graetzel, M. Acc. Chem. Res. 2009, 42, 1788.
[2]
Abbotto, A.; Sauvage, F.; Barolo, C.; De Angelis, F.; Fantacci, S.; Graetzel, M.; Manfredi, N.; Marinzi, C.; Nazeeruddin, M. K. Dalton
Trans. 2011, 40, 234; Abbotto, A.; Barolo, C.; Bellotto, L.; Angelis, F. D.; Gratzel, M.; Manfredi, N.; Marinzi, C.; Fantacci, S.; Yum, J. H.; Nazeeruddin, M. K. Chem. Commun. 2008, 42, 5318.
Development of Iridium-Catalyzed Asymmetric Hydrogenation:
Introduction to Olefin Polymerization Catalysis:
New Catalysts, New Substrate Scope
From Black-Box Systems to Well-Defined High-Activity Catalysts
Pher Andersson
Manfred Bochmann
University Uppsala University, Dep. of Biochemistry&Organic Chemistry, S-75124 Uppsala, Sweden
Wolfson Materials and Catalysis Centre, School of Chemistry, University of East Anglia, Norwich NR4 7TJ, UK.
[email protected]
[email protected]
Enantioselective hydrogenation is one of the most powerful methods in asymmetric catalysis. While ruthenium- and
This contribution will provide an overview of mechanistic aspects of olefin polymerizations with soluble catalysts,
rhodium-catalyzed asymmetric hydrogenations of chelating olefins have a long history, unfunctionalised olefins still
with emphasis on Group 4 metallocene systems. This class of catalysts has proved particularly versatile and is capable of
represent a challenging class of substrates. The corresponding Iridium-catalysed asymmetric hydrogenation are still highly
producing a surprising variety of polymer materials, from highly stereoselective polymers with extreme tensile strengths to
substrate dependent and the development of new efficient chiral ligands that tolerate a broad range of substrates remains a
those incorporating polar groups. Metallocene catalysts include some of the most active catalytic systems ever reported,
challenge.
which, given the right activator and conditions, are capable to generating over 10 5 new C-C bonds per second.
This lecture will deal with the preparation of a new class of chiral heteroaromatic N,P ligands along with their
applications in catalytic asymmetric synthesis.
Topics to be discussed include
–
brief historic introduction;
–
general reaction principles
–
the chemistry of catalyst activation
–
non-coordinating anions and anion engineering
–
The origin of stereospecific polymerizations
–
Polymerization kinetics and the determination of the active species concentration
References
–
Active and dormant states: an approach to the structure of the transition state
[1]
Modern Reduction Methods; Andersson, P. G., Munslow, I. J., Eds.; Wiley-VCH, New York, 2008.
–
Metal alkyl and metal olefin complexes
[2]
Källström, K.; Hedberg, C.; Brandt, P.; Bayer, A.; Andersson, P. G. J. Am. Chem. Soc., 2004, 126, 14308.
–
Chain shuttling and its consequences
[3]
Hedberg, C.; Källström, K.; Arvidsson, P. I.; Andersson, P. G. J. Am. Chem. Soc., 2005, 127, 15083.
Methylaluminoxane as catalyst activator – an approach to its structure and understanding
[4]
Trifonova, A.; Diesen, J. S.; Andersson, P. G. Chem. Eur. J., 2006, 12, 2318.
–
[5]
Hedberg, C.; Källström, K.; Brandt, P.; Bayer, A.; Andersson, P. G. J. Am. Chem. Soc., 2006, 128, 2995.
[6]
Källström, K.; Munslow, I.; Andersson, P.G. Chem. Eur. J., 2006, 12, 3194.
References:
[7]
Engman, M.; Diesen, J.; Andersson, P. G. J. Am. Chem. Soc., 2007, 129, 4536.
The Chemistry of Catalyst Activation: The Case of Group 4 Polymerization Catalysts.
[8]
Cheruku, P.; Diesen, J.; Andersson, P. G. J. Am. Chem. Soc., 2008, 130, 5595.
[9]
Diéguez, M.; Mazuela, J.; Pàmies, O.; Verendel, J.J.; Andersson, P. G. J. Am. Chem. Soc., 2008, 130, 7208.
PAr2
N
R
X
Bochmann, M. Organometallics 2010, 29, 4711.
Kinetic and Mechanistic Aspects of Metallocene Polymerisation Catalysts.
[10] Henriksen, S. T.; Norrby, P.O.; Tolstoy, P.; Andersson, P. G. J. Am. Chem. Soc., 2008, 130, 10414.
Bochmann, M. J. Organomet. Chem. 2004, 689, 3982.
[11] Cheruku, P.; Paptchikhine, A.; Church, T.; Andersson, P. G J. Am. Chem. Soc., 2009, 131, 8285.
The Use of Spectroscopy in Metallocene-Based Polymerisation Catalysis.
[12] Tolstoy, P.; Engman, M.; Paptchikhine, A.; Bergquist, J.; Church.; Leung, A.W.M.; Andersson, P. G J. Am. Chem. Soc., 2009, 131, 8855.
Bochmann, M. in: Catalytic Mechanisms from Spectroscopic Measurements, B. T. Heaton (editor), Wiley-VCH, Weinheim, 2005, p. 311 – 357.
[13] Mazuela, J.; Verendel, J.J.; Coll, M.; Schäffer, B.; Börner, A.B.; Andersson, P. G.; Pàmies, O.; Diéguez, M. J. Am. Chem. Soc., 2009,
131, 12344.
[14] Verendel, J. J.; Zhou, T.; Li, J.-Q.; Paptchikhine, A.; Lebedev, O.; Andersson, P. G. J. Am. Chem. Soc. 2010, 132, 8080.
LECTURES
LECTURES
Metal-Metal Bonds and d10-d10 Interactions
18-electron Rule : Myth or Reality? A Natural Bond Orbital Perspective
Pierre Braunstein
Eric Clot
Institut Charles Gerhardt, CNRS 5253, Université Montpellier 2, Place Eugène Bataillon, 34000 Montpellier, France
Laboratoire de Chimie de Coordination, Institut de Chimie (UMR 7177 CNRS), Université de Strasbourg, 4 rue Blaise Pascal, F-67081
[email protected]
Strasbourg Cédex, France
[email protected]
Any organometallic chemistry textbook presents at the very beginning the 18-electron rule (16-electron rule for square
Complexes containing metal-metal bonds and metal clusters are now very familiar not only to molecular chemists, i.e.
planar complexes) as the cornerstone to rationalize the stability of transition metal complexes. Many catalytic cycles are
coordination and organometallic chemists, but also to specialists of solid-state and physical chemistry since metal-metal
discussed as likely or not based on the presence of highly unsaturated complexes (less than 18-electron or 16-electron)
bonding can occur in molecular compounds, inorganic solids or in the gas phase. [1] The interest for mutual interactions
along the pathway. This 18-electron rule is largely empirical and relies mostly on the assumption that a transition metal
between metal centres with a d10 electronic configuration (d10-d10 interactions) has been growing fast because they had to
will use its nine valence orbitals (nd, (n+1)s and (n+1)p) to create symmetry-adapted bonding combinations with the
involve concepts other than classical covalent or dative bonding. [2] They are best evidenced in the solid state by X-ray
valence orbitals of the ligands and non-bonding orbitals essentially developed on the metal. However, modern theoretical
diffraction which provides precise information about the distance between the metals involved. Numerous theoretical
approaches such as the Natural Bond Orbital method, developed by Weinhold, [1] have implied that the p-orbitals on the
studies on metallophilic interactions continue to be carried out at various levels of sophistication which take into account
metal do not participate significantly to any metal-ligand bonding. Therefore only the 5 nd atomic orbitals together with the
relativistic and correlation effects to describe these van der Waals-type interactions.[3]
(n+1)s orbital are used to create bonds to ligands. The complex is thus saturated when surrounded by 12 electrons (6
We would like to illustrate with some examples the synthesis and structures of heterometallic clusters of the transition
bonding or non-bonding pairs).
metals in which intra- rather than intermolecular d10-d10 interactions are at work, in order to limit the role of packing
This lecture will present the foundations of the dodectet rule as deduced from an NBO analysis of the electronic
effects. Although the focus will be on d10-d10 interactions involving metals from the group 11, we shall also examine for
structure of transition metal complexes. Within this framework, complexes with more than 12 electron are hypervalent and
comparison some complexes displaying intramolecular d10-d10 interactions involving metals from other groups.[4]
it is necessary to introduce a new concept, the 3-center 4-electron -bond, to explain the geometries observed. These
approaches will be used to illustrate the chemical insight that can be obtained in the study of the coordination of ligands
(H2 vs. H2BR) and in catalytic transformations (olefin hydrogenation by Wilkinson’s catalyst).
References
[1] Weinhold, F; Landis, C. R. Valency and Bonding: A Natural Bond Orbital Donor-Acceptor Perspective; Cambridge University Press:
Cambridge, UK, 2005.
Acknowledgment We are grateful to the CNRS, the Ministère de l’Enseignement Supérieur et de la Recherche, the DFH/UFA, the DFG
International Research Training Group GRK532 and the Agence Nationale de la Recherche (ANR-06-BLAN-410) for support of our own
research in this field.
References
[1]
Selected books: P. Braunstein, L. A. Oro and P. R. Raithby, Metal Clusters in Chemistry, Wiley-VCH, Weinheim, 3 vol. 1999. P. J.
Dyson and J. S. McIndoe, Transition metal carbonyl cluster chemistry, Gordon and Breach Science Publishers, 2000. M. Driess and H.
Nöth, Molecular clusters of the main group elements, Wiley-VCH, Weinheim, 2004. T. P. Fehlner, J.-F. Halet and J.-Y. Saillard,
Molecular clusters: a bridge to solid-state chemistry, Cambridge University Press, Cambridge, 2007. A. Laguna, Modern Supramolecular
Gold Chemistry: Gold-Metal Interactions and Applications, Wiley-VCH, Weinheim, 2008.
[2]
Schmidbaur, H.; Schier, A. Chem. Soc. Rev., 2008, 37, 1931. Schmidbaur, H. Chem. Soc. Rev., 1995, 24, 391.
[3]
Pyykkö, P. Angew. Chem., Int. Ed., 2004, 43, 4412. Pyykkö, P. Chem. Soc. Rev., 2008, 37, 1967.
[4]
Sculfort, S.; Braunstein, P. Chem. Soc. Rev., 2011, 40, 2741.
Organometallic Complexes of Transition Metals in Luminescent Cell Imaging
Combined Coinage Metal Catalysis for the Synthesis of Bioactive Molecules
Applications
Norbert Krause
Michael P. Coogan
Dortmund University of Technology, Organic Chemistry, Otto-Hahn-Strasse 6, D-44227 Dortmund, Germany
Department of Chemistry, Cardiff University, CF10 3AT, 02920874066, United Kingdom
[email protected]
[email protected]
Transition metal complexes have in recent years become popular lumophores for application in live cell imaging by
The use of the coinage metals copper, silver, and gold offers tremendous potential for stereoselective target-oriented
fluorescence microscopy. There are several intrinsic photophysical properties associated with phosphorescent transition
synthesis. We are particularly interested in the copper-catalyzed synthesis of α- or β-hetero-substituted allenes from
metal complexes which make them attractive for imaging applications, but there are potential problems in their
applications which must be overcome before they can be applied in living cells. The large difference between excitation
and emission wavelegths (Stokes shift) associated with metal-based lumophores makes it easy to differentiate between the
propargyl electrophiles[1,2] and their goldcatalyzed endo-selective cycloisomerization to 5- or 6-membered heterocycles.[3]
Overall, this sequence enables an efficient Center-to-Axis-to-Center Chirality Transfer.[4] Recent applications of this
Combined Coinage Metal Catalysis include transformations of substrates containing two adjacent allenic π-systems[5] or
signal from the imaging agent and background emission from naturally luminescent parts of the cell (‘autofluorescence’)
heteroatoms,[6] the development of recyclable gold catalysts, [7] and the combination of two catalytic processes in tandem or
which typically has a very small Stokes shift. Many of these complexes also have long luminescence lifetimes, and time-
one-pot reactions.[8-10] These methods have been applied to the stereoselective synthesis of various biologically active target
gating techniques can be used as another method of eliminating autofluorescence which has a short lifetime. Thus, these
complexes are very attractive as imaging agents, but before they can be applied, problems of delivery to cells, membrane
molecules, e. g., the β-carboline alkaloids (−)-isocyclocapitelline and (−)-isochrysotricine,[11] as well as varitriol, bejarol, [12]
and boivinianin B.[13]
permeability and toxicity have to be addressed. These issues are explored as a general introduction to the area before
specific examples of transition metal complexes applied in imaging are addressed.
There are several families of organometallic complexes which have shown promise in this area, most notably iridium
(III) complexes of cyclometallating ligands such as phenyl pyridine 1 and rhenium fac-tricarbonyl biyridines 2 and related
complexes. The synthesis and photophysical properties of these complexes are described in depth, along with illustrative
examples of their application in cell imaging. There are a smaller number of other organometallic complexes of other
metals (Au, Rh) which have been applied in cell imaging which are also described to give a full picture of the current stateof-the-art in this area.
+
N
N
Ir
References
N
[1]
2
(a) Deutsch, C.; Lipshutz, B. H.; Krause, N. Angew. Chem. Int. Ed. 2007, 46, 1650. (b) Deutsch, C.; Lipshutz, B. H.; Krause, N. Org. Lett. 2009, 11, 5010. (c)
Deutsch, C.; Krause, N.; Lipshutz, B. H. Chem. Rev. 2008, 108, 2916.
1
[2]
Tang, X.; Woodward, S.; Krause, N. Eur. J. Org. Chem. 2009, 2836.
[3]
(a) Krause, N.; Aksin-Artok, Ö.; Breker, V.; Deutsch, C.; Gockel, B.; Poonoth, M.; Sawama, Y.; Sawama, Y.; Sun, T.; Winter, C. Pure Appl. Chem. 2010, 82, 1529.
Fig 1. Illustrative Ir(III) complex and a cell imaged with an Ir(III) complex.
+
N
(b) Krause, N.; Winter, C. Chem. Rev. 2011, 111, 1994.
[4]
Bongers, N.; Krause, N. Angew. Chem. Int. Ed. 2008, 47, 2178.
[5]
Poonoth, M.; Krause, N. Adv. Synth. Catal. 2009, 351, 117.
[6]
Winter, C; Krause, N. Angew. Chem. Int. Ed. 2009, 48, 6339.
[7]
(a) Aksin, Ö.; Krause, N. Adv. Synth. Catal. 2008, 350, 1106. (b) Winter, C.; Krause, N. Green Chem. 2009, 11, 1309. (c) Minkler, S. R. K.; Lipshutz, B. H.; Krause,
N. Angew. Chem. Int. Ed. 2011, DOI:10.1002/anie.201101396.
OC
N
Re
OC
N
[8]
Asikainen, M.; Krause, N. Adv. Synth. Catal. 2009, 351, 2305.
[9]
(a) Belot, S.; Vogt, K. A.; Besnard, C.; Krause, N.; Alexakis, A. Angew. Chem. Int. Ed. 2009, 48, 8923. (b) Belot, S.; Quintard, A.; Krause, N.; Alexakis, A. Adv.
Synth. Catal. 2010, 352, 667.
CO
2
Fig 2. Illustrative Re(I) complex and a cell imaged with an Re(I) complex.
[10]
Aksin-Artok, Ö.; Krause, N. Adv. Synth. Catal. 2011, 353, 385.
[11]
(a) Volz, F.; Krause, N. Org. Biomol. Chem. 2007, 5, 1519. (b) Volz, F.; Wadman, S. H.; Hoffmann-Röder, A.; Krause N. Tetrahedron 2009, 65, 1902.
[12]
Sawama, Y.; Sawama, Y.; Krause, N. Org. Biomol. Chem. 2008, 6, 3573.
[13]
Miura, T.; Shimada, M.; De Mendoza, P.; Deutsch, C.; Krause, N.; Murakami, M. J. Org. Chem. 2009, 74, 6050.
LECTURES
LECTURES
Investigations in Stereoselective Synthesis and Catalysis
Ru Based Molecular Complexes as Catalysts for the Oxidation of Water to Dioxygen
Jérôme Lacour
Antoni Llobet
University of Geneva, Quai Ernest Ansermet 30, 1211 Genève 4, Switzerland
Institute of Chemical Research of Catalonia (ICIQ), Avinguda Països Catalans 16, E-43007 Tarragona, Spain. b Departament de Química
[email protected]ch
Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193 Barcelona, Spain
[email protected]
The main research interest of the group is stereoselective chemistry in a wide sense. Current research programs cover
Oxygen-Oxygen bond formation is the key step for the oxidation of water to molecular oxygen: a reaction of interest
a variety of topics within the areas of enantioselective catalysis, stereoselective synthesis, asymmetric recognition, NMR
enantiodifferentiation, and these encompass the use of a large range of original ionic compounds and metal complexes. In
from a biological perspective and also for establishing new energy conversion schemes. A few Ru complexes have been
the context of ISOC-11, recent studies on metal-catalyzed reactions and processes are presented – and those involving
described recently that are capable of catalyzing the water oxidation reaction, and their performance has been shown to be
Rh(II)-catalyzed decompositions of α-diazo-β-ketoesters in particular.
strongly dependent on, nuclearity, oxidation state and ligand topology.[1]
For instance, 15-, 16- and 18-membered polyether macrocycles are prepared in a single step from condensation
reactions with cyclic ethers. Against conventional wisdom, these macrocyclizations of four separate components occur
under nontemplated conditions and are more efficient as the concentration is increased. [1] Also, new configurationallystable ethano-Tröger bases can be prepared in a single step using novel carbenoid chemistry. The process is general,
enantiospecific (ee up to 99%), diastereoselective (with a new quaternary carbon center introduction, dr up to 49:1) and
regioselective.[2]
Figure. (1,2)-O2-Ru2-L transition state that leads to the formation of molecular oxyen. Color codes. Ru, yellow; peroxo-O, red; aqua-O blue marine; C, Grey, N, light blue;
H, white.
A step forward in the field consists on unravelling the different reaction pathways trough which these reactions
proceed. We have tackled this challenging topic by carrying out thorough electrochemical, spectroscopic and kinetic
[CpRu(CH3CN)3][PF6][3] and diimine ligands catalyze also the decomposition of α-diazoacetoacetates leading to O-H
insertion and condensation reactions. In comparison with Rh(II) and Cu(I) complexes, the CpRu catalysts produce rapid
and often more selective reactions. Promising enantioselectivities are obtained in dioxole syntheses. [4] Other reactions and
analysis together with O-18 labeling studies and DFT calculations. The combination of all these results gives evidence for
mechanisms involving: intramolecular O-O bond formation, water nucleophilic attack and bimolecular O-O bond
formation.[2]
processes involving [CpRu(CH3CN)3][PF6] will be presented.[5]
References:
[1]
References
[1]
Zeghida, W.; Besnard, C.; Lacour, J. Angew. Chem. Int. Ed. 2010, 49, 7253. Rix, D.; Ballesteros-Garrido, R.; Zeghida, W.; Besnard, C.;
Lacour, J. Angew. Chem. Int. Ed. 2011, 50, DOI: 10.1002/anie.201102152.
[2]
Sharma, A. ; Guénée, L. ; Naubron, J.-V.; Lacour, J. Angew. Chem. Int. Ed. 2011, 50, 3677.
[3]
Kündig, E. P.; Monnier, F. R. Adv. Synth. Catal. 2004, 346, 901. Mercier, A.; Yeo, W. C.; Chou, J.; Chaudhuri, P. D.; Bernardinelli, G.;
Kundig, E. P. Chem. Commun. 2009, 5227.
[4]
Austeri, M. ; Rix, D. ; Zeghida, W. ; Lacour, J. Org. Lett. 2011, 13, 1394.
[5]
Austeri, M.; Linder, D.; Lacour, J. Adv. Synth. Catal. 2010, 352, 3339. Austeri, M.; Linder, D. ; Lacour, J. Chem. Eur. J. 2008, 14, 5737.
Constant, S. ; Tortoioli, S. ; Müller, J. ; Linder, D. ; Buron, F. ; Lacour, J. Angew. Chem. Int. Ed. 2007, 46, 8979. Constant, S.; Tortoioli,
S.; Müller, J.; Lacour, J. Angew. Chem. Int. Ed. 2007, 46, 2082.
(a) Sala, X.; Rodriguez, M.; Romero, I.; Escriche, L.; Llobet, A. Angew. Chem. Int. Ed. 2009, 48, 2842. (b) Romain, S.; Vigara, L.; Llobet, A. Acc. Chem. Res. 2009,
42, 1944-1953.
[2]
(a) Sens, C.; Llobet, A. et al. J. J. Am. Chem. Soc. 2004, 126, 7798. (b) Mola, J.; Llobet, A. et al. Angew. Chem. Int. Ed. 2008, 47, 5830-5832. (c) Romain, S.;
Bozoglian, F.; Sala, X.; Llobet, A., J. Am. Chem. Soc. 2009, 131, .2768. (d) Bozoglian, F.; Romain, S.; Ertem, Cramer, C. J.; Gagliardi, L.; Llobet, A. et al. J. Am.
Chem. Soc. 2009, 15176-15187. (e) Sartorel, A.; Miró, P.; Llobet, A.; Bo, C.; Bonchio, M. et al. J. Am. Chem. Soc. 2009, 16051–16053. (f) Sala, X.; Ertem, M. Z.;
Cramer, C. J.; Gagliardi, L.; Llobet, A. et al. Angew. Chem. Int. Ed. 2010, 49, 7745-7747. (g) Planas, N.; Christian, G. J.; Mas-Marza, E.; Sala, X.; Fontrodona, X.;
Maseras, F.; Llobet, A., Chem. Eur. J. 2010, 16, 7965–7968.
Recent Advances in Stereoselective Synthesis
Organometallic Derivatives as Smart Materials for Optoelectronics
Ilan Marek
Regis Réau
The Mallat Family Laboratory of Organic Chemistry, Schulich Faculty of Chemistry and the Lise Meitner-Minerva Center for Computational
Université de Rennes1, CNRS, UMR 6226, Sciences Chimiques de Rennes, campus de Beaulieu, 35042 Rennes cedex,
Quantum Chemistry. Technion-Israel Institute of Technology. Haifa, 32000 Israel
[email protected], www.scienceschimiques.univ-rennes1.fr/equipes/om2/phosphore-materials-molecular
[email protected]
-Conjugated oligomers and polymers based on organometallic [1] and main-group elements (P, Si…)[2] have attracted
In the past several decades, impressive progress has been made in the field of stereoselective synthesis and a myriad
strong interest in recent years owing to their potential applications for electronic devices (light emitting diodes, thin film
of beautiful synthetic transformations have appeared. However, among the remaining significant challenges in chemical
transistors, photovoltaïc cells...).[3] The tailoring of these semi-conducting organic materials for improving their
sciences, the development of new strategies for the enantioselective creation of carbon atoms bonded to four different
electrochemical and optical properties towards plastic electronic applications necessitates extensive experimental
carbon substituents remains (all-carbon quaternary centers).1 The creation of such centers is complicated by steric repulsion
molecular engineering. Using building blocks based on organometallic and main-group moieties (such as siloles A,
between the carbon substituents and the state-of-the art would be the enantioselective construction of quaternary all-carbon
phosphole B or orthometalled complexes C) allow developing original approaches that are not possible using classic
stereogenic centers in acyclic systems. In the last few years, we have been involved in the development of synthetic
organic chemistry. Selected examples will be presented to illustrate this molecular engineering of -conjugated systems.
strategies that led to the formation of these desired fragments with very interesting stereochemical outcome, and we have
Approaches going from the study of molecular species, in order to establish structure-property relationship, to functional
particularly focused our recent efforts on the concomitant creation of several carbon-carbon bonds in a single-pot
material that can be used in optoelectronic devices will be illustrated. Lastly, the use of organometallic and phosphorus
operation.2 In the first lecture, we will particularly concentrate on the allylation and aldol reactions. The latter case is very
chemistry for the tailoring of helicene derivatives towards materials exhibiting hudge chiroptical properties will be
interesting since aldol adducts possessing an all-carbon quaternary stereogenic center is relatively rare by the need for and
described.[4]
inability to obtain geometrically defined α,α-disubstituted enolate or enolate equivalents. In the second lecture, we will
demonstrate that strained double bond can also be easily manipulated to lead similarly to the creation of all-carbon
quaternary centers.
R1
References
R4
R3
[1] (a) Baldo, M. A.; Thompson, M. E.; Forrest, S. R. Nature 2000, 403, 750. (b) Le Bozec, H.; Guerchais, V. Molecular Organometallic
R2
Materials for Optics, Topics in Organometallic Chemistry series, Springer, 2009. (c) Yersin, H. (ed.) Highly Efficient OLEDs with
Phosphorescent Materials, Wiley VCH, 2008.
[2]
(a) Baumgartner, T.; Réau, R. Chem. Rev. 2006, 106, 4681. (b) Yamaguchi, S.; Tamao, K. J. Chem. Soc., Dalton Transactions 1998, 22,
3693.
[3]
References
(a) Müllen, K.; Scherf, U. (Eds:), Organic Light Emitting Devices: Synthesis Properties and Applications, Wiley-VCH, Weinheim,
Org. Lett. 2011, 13, DOI: 10.1021/ol201221d; Chem. Eur. J. 2011, 17, DOI: 10.1002/chem.201101049; Chem. Commun. 2011, 47, 4593; J.
Germany 2006. (b) Müllen, K.; Wegner, G. Electronic Materials: The Oligomer Approach; Wiley-VCH, Weinheim, 1998. (c) Skotheim,
Am. Chem. Soc. 2010, 132, 5588; J. Am. Chem. Soc. 2010, 132, 4066; Chem. Eur. J. 2010, 16, 774; Chem. Eur. J. 2010, 16, 9712; Chem. Eur.
T. A.; Elsenbaumer, R. L.; Reynolds, J. R. Handbook of Conducting Polymers, 2nd ed.; Dekker: New York, 1998. (d) Cheng, Y.-J.;
J. 2009, 15, 8449; Nature Chem. 2009, 1, 128; Chem. Eur. J. 2008, 14, 7460; Angew. Chem. Int. Ed. 2008, 47, 6865-6868; Angew. Chem. Int.
Yang, S.-H.; Hsu, C.-S. Chem. Rev. 2009, 109, 5868. (e) Grimsdale, A.; Chan, K. L.; Martin, R. E.; Jokisz, P. G.; Holmes, A. B. Chem.
Rev. 2009, 109, 897.
Ed. 2007, 46, 8039; Chem. Commun, 2007, 1683; Angew. Chem. Int. Ed. 2007, 43, 7364; J. Am. Chem. Soc. 2006, 128, 4642.
[4]
(a) Norel, L.; Rudolph, M.; Vanthuyne, N.; Williams, J. A. G.; Lescop, C.; Roussel, C.; Auchtsbach, J.; Crassous, J.; Réau, R. Angew.
Chem. Int. Ed. 2010, 49, 99. (b) Anger, E.; Rudolph, M.; Shen, C.; Vanthuyne, N.; Toupet, L.; Roussel, C.; Autschbach, J.; Crassous, J.;
Réau, R. J. Am. Chem. Soc. 2011, 133, 3800. (c) Graule, S.; Rudolph, M.; Vanthuyne, N.; Autschbach, J.; Roussel, C.; Crassous, J.; Réau,
R. J. Am. Chem. Soc. 2009, 131, 3183. (d) Graule, S.; Rudolph, M.; Shen, W.; Lescop, C.; Williams, J. A. G.; Autschbach, J.; Crassous,
J.; Réau, R. Chem. Eur. J. 2010, 16, 5976.
LECTURES
LECTURES
Solar Energy Conversion by Molecular Catalysts Inspired by the Active Sites of
Artificial Metalloenzymes: Enantioselective Catalysis and Beyond
Photosystem II and [FeFe]-Hydrogenase
Thomas R. Ward
Licheng Sun
Department of Chemistry, University of Basel, Spitalstrasse 51, CH-4056 Basel Switzerland
Department of Chemistry, School of Chemical Science and Engineering, Royal Institute of Technology (KTH), 10044 Stockholm, Sweden,
[email protected]
[email protected]
Inspired by the structure and function of Photosystem II (PSII) and [FeFe]-Hydrogenases, we have designed and
synthesized a series of molecular catalysts by mimicking the active sites of these enzymes. Visible light driven hydrogen
generation has been achieved in supramolecular systems consisting of Fe2S2 or Co catalysts and photosensitizers. For
water oxidation, Mn complexes and Ru complexes by using negatively charged ligands have been designed and
synthesized. In particular, the molecular Ru complexes have been demonstrated to be highly efficient catalysts towards
water oxidation in homogeneous systems driven either by chemical oxidants or by visible light in combination with
photosensitizers. Some of the Ru water oxidation catalysts have reached the turnover frequency which is close to natural
PSII. Based on the working principles of dye-sensitized solar cells (DSCs), we are going to move these two half reactions
one step further by making similar devices as DSCs in which molecular catalysts for water oxidation and hydrogen
generation will be integrated with respective anode and cathode electrode materials. Details on the possible reaction
mechanisms for the catalytic O-O bond formation, H-H bond formation and immobilization of these catalysts to respective
electrode surfaces will be presented in this lecture.
Artificial metalloenzymes are created by incorporating an
organometallic catalyst within a host protein. The resulting
hybrid can thus provide access to the best features of two
distinct, and often complementary, systems: homogeneous and
enzymatic catalysts. The coenzyme may be positioned with
covalent, dative, or supramolecular anchoring strategies.
Although initial reports date to the late 1970s, artificial
metalloenzymes for enantioselective catalysis have gained
significant momentum only in the past decade, with the aim of
complementing homogeneous, enzymatic, heterogeneous, and
organic catalysts. Inspired by a visionary report by Wilson and
Whitesides in 1978, we have exploited the potential of biotin–
avidin technology in creating artificial metalloenzymes. Owing
to the remarkable affinity of biotin for either avidin or streptavidin, covalent linking of a biotin anchor to a catalyst
precursor ensures that, upon stoichiometric addition of (strept)avidin, the metal moiety is quantitatively incorporated within
the host protein. In this presentation, we review our progress in preparing and optimizing these artificial metalloenzymes,
beginning with catalytic hydrogenation as a model and expanding from there. These artificial metalloenzymes can be
optimized by both chemical (variation of the biotin-spacer ligand moiety) and genetic (mutation of avidin or streptavidin)
means. Such chemogenetic optimization schemes were applied to various enantioselective transformations. The reactions
implemented thus far include the following: (i) The rhodium–diphosphine catalyzed hydrogenation of N-protected
dehydroaminoacids. (ii) The palladium-diphosphine catalyzed allylic alkylation of 1,3-diphenylallylacetate. (iii) The
ruthenium pianostool-catalyzed transfer hydrogenation of prochiral ketones and imines. (iv) The vanadyl-catalyzed
oxidation of prochiral sulfides. (v) The osmium catalysed dihydroxylation of olefins. A number of noteworthy features are
reminiscent of homogeneous catalysis, including straightforward access to both enantiomers of the product, the broad
substrate scope, organic solvent tolerance, and an accessible range of reactions that are typical of homogeneous catalysts.
Enzyme-like features include access to genetic optimization, an aqueous medium as the preferred solvent, Michaelis–
References
Menten behaviour, and single-substrate derivatization. The X-ray characterization of artificial metalloenzymes provides
[1]
Y. Gao, T. Åkermark, J. Liu, L. Sun, B. Åkermark, J. Am. Chem. Soc. 2009, 131, 8726.
fascinating insight into possible enantioselection mechanisms involving a well-defined second coordination sphere
[2]
L. Duan, A. Fischer, Y. Xu, L. Sun, J. Am. Chem. Soc. 2009, 131, 10397.
[3]
J. Nyhlén, L. Duan, B. Åkermark, L. Sun, Timofei Privalov, Angew. Chem. Int. Ed. 2010, 49, 1773.
[4]
Y. Xu, A. Fischer, L. Duan, L. Tong, B. Åkermark, L. Sun, Angew. Chem. Int. Ed. 2010, 49, 8934.
[5]
H. Tian, X. Jiang, Z. Yu, L. Kloo, A. Hagfeldt, L. Sun, Angew. Chem. Int. Ed. 2010, 49, 7328.
this strategy can be extended to selectively binding streptavidin-incorporated biotinylated ruthenium pianostool complexes
[6]
A. Hagfeldt, G. Boschloo, L. Sun, L. Kloo, H. Pettersson, Chem. Rev. 2010, 110, 6595.
to telomeric DNA. This application paves the way for chemical biology applications of artificial metalloenzymes.
7]
L. Tong, L. Duan, Y. Xu, T. Privalov, L. Sun, Angew. Chem. Int. Ed. 2011, 50, 445.
environment. Thus, such artificial metalloenzymes combine attractive features of both homogeneous and enzymatic
kingdoms. In the spirit of surface borrowing—that is, modulating ligand affinity by harnessing existing protein surfaces—
SPONSORS
POSTERS
Poster 1
Poster 2
Palladium(II) Allyl Complexes of a Dendritic Ligand Containing 4-(2-Pyridil)-1,2,3-
Synthesis of alkyl-vinyl-ethers and Platinum hydrides by-hydride shift in
Triazole Moieties
[Pt(X)(N-N)(1-CH2CH2OR)] complexes
M. Aversa,* E. Amadio, M. Bertoldini, G. Chessa, A. Scrivanti
Daniela Antonucci,* Michele Benedetti, Francesco P. Fanizzi
Dipartimento di Scienze Molecolari e Nanosistemi, Università Cà Foscari di Venezia, Calle Larga S. Marta 2137, 30123 Venezia, Italy
Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Via Monteroni, 73100 Lecce, Italy,
*[email protected]
*daniela.a[email protected]
Recently, it has been reported that the cationic complex [Pd(η3-C3H5)(2-((4-phenyl-1H-1,2,3-triazol-1-yl)methyl)Large interest is nowadays devoted to the industrial applications of alkyl-vinyl-ethers. Unfortunately these low toxic
monomers, useful to prepare adhesives and polymeric materials, are characterized by high production costs.[1]
pyridine)](BF4) exhibits good activity in the Suzuki-Miyaura coupling of aryl bromides with phenyl boronic acid.[1] The
pyridil-1,2,3-triazole ligand was synthesized using the copper catalyzed [3+2] azide-alkyne Huisgen reaction. This reaction
We previously studied the Zeise’s anion basic hydrolysis patterns, in alcoholic solvents (ROH), [2] demonstrating that,
emerged in the last decade as a powerful tool to synthesize 1,2,3-triazoles under mild reaction conditions and with almost
after the initial stepwise substitution of chlorides, there is a possible nucleophilic attack of an alcoholate to the 2-
quantitative yields allowing to obtain a wide variety of 1,2,3,-triazoles ligands.[2] Aiming at incorporate palladium allyl
coordinated ethene. Exploiting such a reactivity, we were able to synthesize the complex [PtCl(Me 2Phen)(1-CH2CH2OR)],
complexes in dendritic structures we have prepared a dendritic ligand (1) based on triphenylamino moiety.
1, Me2Phen = 2,9-dimethyl-1,10-phenantroline; R = Alkyl.[2-4] In this work we report a new reaction pathway, for the high
The synthesis of (1) was achieved, starting from triphenylamine, by a six-step sequence: Vilsmeier reaction, ioduration,
yields synthesis, of alkyl-vinyl-ethers, starting from an alcohol, Me2Phen and Zeise’s salt by formation of
reduction, double Sonogashira coupling with ethynyltrimethylsilane, deprotection and Huisgen type [3+2] cycloaddiction
[Pt(X)(Me2Phen)(1-CH2CH2OR)], X = Cl (1), Br (2), I (3) derivatives. The synthesis of vinyl ethers can be obtained by
with 2-picolylazide.
slow spontaneous decomposition of type 1 complexes, in organic solvents, as a result of a -hydride shift process (Figure 1).


Addition of Br or I to a solution of 1 gives complexes 2 and 3, respectively, which are fast decomposing unstable
Finally, the reaction between (1) and the palladium precursor [PdCl(C3H5)]2 gives the desired complex (2) which has
been fully characterized by multinuclear NMR spectroscopy.
intermediates (decomposition rate: 3 > 2 > 1), leading to the corresponding vinyl ethers CH2=CHOR and the square planar
complex [Pt(X)H(Me2Phen)] (Figure 1).
Interestingly analogous complexes of the type [PtCl(N-N)(CH2CH2OR)], N-N = 1,10-phenantroline or 2,2’-bipyridine,
are indefinitely stable both in solution and in the solid state. This demonstrates that in these systems for the -hydride shift
process the presence of a carrier ligand, such as Me2Phen, able to introduce a strong sterical hindrance in the Pt(II)
coordination plane, is strictly required.
Figure 1. Synthesis of the palladium (II) complex
References
[1]
Figure 1
388.
[2]
References
[1]
Modjewski, R. J. Radtech Report May/June 1999, 45-48.
[2]
(a) Benedetti, M.; Fanizzi, F. P.; Maresca, L.; Natile, G. Chem. Commun. 2006, 1118. (b) Vecchio, V.M; Benedetti, M.; Migoni, D.; De
Pascali, S. A.; Ciccarese, A.; Marsigliante, S.; Capitelli, F.; Fanizzi, F. P. Dalton Trans 2007, 5720. (c) Barone, C. R.; Benedetti, M.;
Vecchio, V.M.; Fanizzi, F. P; Maresca, L.; Natile, G.. Dalton Trans 2008, 5313.
[3]
Joy, Von J. R.; Orchin, M. Fresenius’ Z. Anal. Chem. 1960, 305, 236.
[4]
(a) Huston, A. C.; Lin, M.; Basickes, N.; Sen, A. J. Organomet. Chem., 1995, 504, 69. (b) Luinstra, G. A.; Wang, L.; Stahl, S. S.;
Labinger, J. A. and Bercaw, J. E. J. Organomet. Chem., 1995, 504, 75.
Amadio, E.; Bertoldini, M.; Scrivanti, A.; Chessa, G.; Beghetto, V.; Matteoli, U.; Bertani, R.; Dolmella, A. Inorg. Chim. Acta, 2011, 370,
Struthers, H.; Mindt, T. L.; Schibli, R. Dalton Trans., 2010, 39, 675.
Poster 3
Poster 4
Multinuclear NMR study of PH2P(BH3)Li in THF-d8 solution: new aspects on the
reactivity of P-alkylation and reduction reactions
Fluorescent Chemosensors for Anion Based on Uranyl-Salophen and Salen
Silvia Bartocci,a* Antonella Dalla Cort,a Luca Schiaffino,b Francesco Yafteh Mihana
Gabriella Barozzino Consiglio,a,b* Pierre Queval,c Anne Harrison-Marchand,a Alessandro Mordini,b Jean-
a
François Lohier,c Olivier Delacroix,c Annie-Claude Gaumont,c Hélène Gérard,d Jacques Maddaluno,a Hassan
b
Oulyadia
a
b
*[email protected]
CNRS UMR 6014 & 3038, Université de Rouen and INSA de Rouen, 76821 Mont St Aignan Cedex, France,
In recent years the development of highly sensitive and selective fluorescent chemosensory materials has received
ICCOM-CNR, Dipartimento di Chimica “U. Schiff”, Università di Firenze, Via Della Lastruccia 13, 50019 Sesto Fiorentino, Firenze, Italy, c
Laboratoire de Chimie Moléculaire et Thio-organique, CNRS UMR 6507 & FR 3038, ENSICAEN and Université de Caen, 14050 Caen, France,
d
Department of Chemistry, University of Rome “La Sapienza”
Department of Science and Chemical Tecnologies, University of Rome “ Tor Vergata”
much attention. In particular, the design of such systems capable of detecting anions is a target of major importance because
of the role that anions play in several biological processes, [1] and as pollutants.
CNRS UMR 7676, LCT, UPMC Université Paris 6, 4 place Jussieu, 75252 Paris Cedex 05, France, *[email protected]
Uranyl salophen complexes are strong Lewis acids that strongly bind anions in organic solvents and, if properly
P-chiral phosphide-boranes have been shown to be valuable building blocks in the synthesis of enantiomerically pure
functionalized, in water.[2] The recognition event is easily detected by variations in the UV-vis spectra. Although these
phosphines with chirogenic phosphorus centers.1 However, despite the considerable interest towards these compounds no
complexes do not show photoluminescent emission, which is very useful for chemosensing; the introduction of appropriate
information about their structure and their stability in solution is present in the literature.
fluorophores in the backbone of the salophen ligand can provide such property.
For this reason a set of heteronuclear (1H, 6Li, 11B, 13C and 31P) NMR experiments in THF-d8 has been conducted on a
lithium borylphosphide model: lithium diphenylphosphide borane 1 (Figure 1). These experiments have clearly established
Here we report the synthesis of two new uranyl-salophen complexes that show photoluminescent properties and the
preliminary binding study of the association with selected anions.
that the deprotonation of diphenylphosphine-borane by n-BuLi in THF leads to a disolvated monomer with the lithium
cation connected to the hydrides on the boron and two THF molecules. These structural data allowed us also to understand
some aspects of its reactivity in the field of P-alkylation and reduction reactions of carbonyl species.
-78°C
BH3
P
Ph
H
Ph
n-BuLi
THF
-78°C
Ph
H
P B H
Ph
H
Li
O
O
R1
O
1
R2
THF
BH3
Ph P
Ph
R1
OH
R2
OH
rt
2
H 1 R
R
Figure 1
Figure 1
References
References
[1]
Kim, S. K.; Lee, D. H.; Hong, J.-I.; Yoon, J. Acc. Chem. Res., 2009, 42, 23.
[1] See for example: (a) Williams, B. S.; Dani, P.; Lutz, M.; Spek, A. L.; van Koten,G. Helv. Chim. Acta 2001, 84, 3519.Slunt, K. M.;
[2]
Dalla Cort, A.; De Bernardin, P.; Forte, G.; Yafteh Mihan, F. Chem. Soc. Rev., 2010, 39, 3863.
Giancarlo, L. C. J. Chem. Educ. 2004, 81, 985-988. (b) Wolfe, B.; Livinghouse, T. J.Org. Chem. 2001, 66, 1514. (c) Wolfe, B.;
Livinghouse, T. J. Am. Chem.Soc. 1998, 120, 5116. (d) Ohff, M.; Holz, J.; Quirmbach, M.; Börner, A. Synthesis 1998, 1391 (review). (e)
Imamoto, T.; Matsuo, M.; Nonomura, T.; Kishikawa, K.; Yanagawa, M.; Heteroat. Chem. 1993, 4, 475. (f) Imamoto, T.; Oshiki, T.;
Onozawa, T.; Matsuo, M.; Hikosaka, T.; Yanagawa, M. Heteroat. Chem. 1992, 3, 563. (g) Oshiki, T.; Hikosaka, T.; Imamoto, T.
Tetrahedron Lett. 1991, 32, 3371. (h) Imamoto, T.; Oshiki, T.; Onozawa, T.; Kusumoto, T.; Sato, K. J. Am. Chem. Soc. 1990, 112, 5244.
POSTERS
POSTERS
Poster 5
Poster 6
Regioselective ring closing ene-yne metathesis for the synthesis of highly
Quantitative Investigation of Thermodynamic Template Effect
functionalizable benzazepine scaffolds
Josè Augusto Berrocal,* Roberta Cacciapaglia, Stefano Di Stefano, Luigi Mandolini
Erica Benedetti,
a,b,*
a
a
b
Michela Lomazzi, Francesco Tibiletti, Jean-Philippe Goddard, Louis Fensterbank,
b
Max Malacria,b Giovanni Palmisanoa and Andrea Penoni a,
CNR-IMC Sezione Meccanismi di Reazione and Department of Chemistry Università di Roma La Sapienza, P.le Aldo Moro 5, 00185 Roma,
*[email protected]
a
Institut Parisien de Chimie Moléculaire (IUMR CNRS 7201) – FR 2769 UPMC univ Paris 06, C. 229, 4 Place Jussieu, 75005, Paris, France.
Macrocyclization reactions under thermodynamic control are at the basis of Dynamic Combinatorial Chemistry (DCC)
Dipartimento di Scienze Chimiche e Ambientali, Università degli Studi dell’Insubria, 11 Via Valleggio, 22100, Como, Italy.
b
since most of the receptors involved are cyclic species. [1-3] The highly appealing feature of a Dynamic Library (DL) is the
*[email protected]
ability to readjust the product distribution upon addition of a template, i.e. a molecule or an ion capable to selectively
Benzazepines, benzoannelated seven-membered nitrogen heterocycles, are ubiquitous constituents in modern
stabilize by binding one or more of its members. The addition of a template for a particular member (target) of the DL
pharmaceuticals or natural products.[1] The structural complexity and biological importance of these molecules recently
generally enhances the total concentration of that member and increases its yield. An “amplification” of the target is said to
prompted organic chemists to discover novel methodologies for their synthesis.
occur. In analogy with the kinetic template effect (kte) defined for macrocyclization reactions under kinetic control, [4] a
In the last few year, olefin metathesis has emerged as a versatile synthetic technique, revolutionizing the area of
thermodynamic template effect (tte) on a DL of acetalic cyclophanes (Figure 1) will be defined in this communication in
medium-size rings construction.[2] In this context, we report new regioselective ring closing ene-yne metathesis, in which
order to operatively quantify the amplification of a target due to its template. The numerical value of such tte does not
different functionalized 1-benzazepines were formed. Our convenient synthetic protocol also allowed the easy formation of
depend on the experimental conditions but only on the thermodynamic properties of the macrocycle and of its complex with
a 2-benzazepine framework, extending the general scope of the reaction. Finally, we demonstrated with three
the template.
representative transformations that the primary metathesis products can be further functionalized, easily achieving higher
molecular complexity.
[3]
Efforts in the use of RCEYM to obtain natural compounds showing important biological or
pharmacological activities are currently in progress in our laboratory.
Catalyst (3%)
Toluene, N2 ,
O
N
O
R
21-57% yields
N
70°C, 2-5h
(0.02M)
R
Figure 1
O
O
N
Catalyst (3%)
Toluene, N2 ,
N
74% yield
70°C, 2h
(0.02M)
Scheme 1
References
[1]
For selected reviews, see: (a) Horton, D. A.; Bourne, G. T.; Smythe, M. L. Chem. Rev. 2003, 103, 893; (b) Brase, S.; Gil, C.; Knepper, K.
Bioorg. Med. Chem. 2002, 10, 2415.
[2]
For a selected review; see Chattopadhyay, S. K.; Karmakar, S.; Biswas, T.; Majumdar, K. C.; Rahaman, H.; Roy, B. Tetrahedron 2007,
63, 3919.
[3]
Benedetti, E.; Lomazzi, M.; Tibiletti, F.; Goddard, J.-P.; Fensterbank, L.; Malacria, M.; Palmisano, G.; Penoni A.; Tetrahedron,
submitted.
References
[1]
Corbett, P. T.; Leclaire, J.; Vial, L.; West, K. R; Wietor, J.-L.; Sanders, J. K. M.; Otto, S. Chem. Rev. 2006, 106, 3652.
[2]
“Dynamic Combinatorial Chemistry”, Reek J. N. H. & Otto S. editors, 2010, John Wiley & Sons, Inc.
[3]
Di Stefano, S. J. Phys. Org. Chem. 2010, 23, 797.
[4]
Illuminati, G.; Mandolini, L.; Masci, B. J. Am. Chem. Soc. 1983, 105, 555.
Poster 7
Poster 8
Study of catalytic intermediates of the rhodium-catalyzed hydroamination of ethylene
A Photomodulable organometallic catalyst
Aurélien Bethegnies,a Ladislava Levina,b Natalia Belkova,b Oleg Filipov,b
Giulio Bianchini,* Alessandro Scarso, Giorgio Strukul
Jean-Claude Daran,a Rinaldo Polia,c*
a
Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari di Venezia, Calle Larga S. Marta 2137, 30123, Venezia,
Laboratoire de chimie de coordination (lié par convention à l’université Paul Sabatier et à l’Institut National Polytechnique de Toulouse),
*[email protected]
CNRS UPR 8241, 205 route de Narbonne, 31077 Toulouse cedex 4, Franc,
b
A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russia,
c
In homogeneous catalysis proper functionalization of a metal center with an appropriate ligand system often
Institut Universitaire de France, 103, bd Saint-Michel, 75005 Paris, France,
represents the most rewarding strategy to achieve the best performance, in terms of activity, selectivity and sometimes
*[email protected]
recycle. Alternatively the performance of a homogeneous catalyst can be modulated by means of interaction with external
stimuli, mimicking what occurs in Nature where the activity of enzymes is triggered on and off as a function of the request
The direct addition of an amine N-H bond to a carbon-carbon double bond to obtain higher amines (olefin
hydroamination) is an atom economical process that currently attracts much attention. Important advances have been made
for the intramolecular version as well as for the intermolecular reaction involving activated alkenes, whereas the
intermolecular hydroamination of non activated alkenes, such as ethylene, remains a great challenge.
of the organism. A possible approach exploits supramolecular interactions (host-guest) between the catalytic species and
another chemical entity which interact as a second sphere ligand. [1] In this case the restoration of the original activity
requires the addition of a third chemical species. A more simple system can be obtained if considering the light as effector
in catalysis.[2] The preparation of an organometallic complex bearing a molecular tag that undergoes a photochemical
We are interested in the hydroamination of ethylene by aniline catalyzed by rhodium complexes. The reaction
operates under ethylene pressure at 150°C. The precursor catalyst, RhCl3.3H2O, is introduced together with
reaction could deliver a new generation of homogeneous catalysts whose activity, selectivity and recycle properties can be
tailored by employing an appropriate light source.[3]
triphenylphosphine and a phosphonium salt, n-Bu4PI. The combination of these two compounds is necessary for optimum
catalytic activity, yielding several products as shown below.[1]
In the present contribution are presented the synthesis, the light induced behavior and preliminary results in
homogeneous catalysis of a series of new generation soft Lewis acid Pt(II) complexes bearing a coumarinic moiety in the
phosphane ligand. Such species undergo reversible 2+2 photo-cycloaddition if irradiated at the proper wavelength
changing both their steric and geometrical properties. One of these systems demonstrated a high catalytic activity
NH2
RhCl3 -3H2O 1eq
C2H4
Aniline
350eq
Ethylène
700eq
PPh3 2eq
n-Bu4PI 65eq
96h, 150°C
NH
N
difference between its light un-reacted and reacted forms in the alkene isomerization reaction.
N
N-Ethylaniline N,N-Diéthylaniline Quinaldine
Conversion>90%
In this communication, we will report synthetic studies of potential intermediates. These compounds have been
characterized and studied in terms of different equilibria involving the species available in the catalytic medium (aniline,
ethylene, I-, PPh3) using spectroscopic techniques (IR, NMR), in combination with DFT calculations.
Acknowledgment We thank the “Centre National de la Recherche Scientifique » (CNRS), the “Agence Nationale de la Recherche » (ANR-09BLANC-0032-01) and the GDRI « Catalyse Homogène pour le Développement Durable » for financing this study.
References
References
[1]
[1]
Cavarzan, A.; Scarso, A.; Sgarbossa, P.; Strukul, G.; Reek, J. N. H. J. Am. Chem. Soc.2011, 133, 2848.
[2]
Hetch, S.; Stoll, R. S. Angew. Chem. Int. Ed. 2010, 49, 5054.
[3]
Liu, G.; Wang, J. Angew. Chem. Int. Ed. 2010, 49, 4425.
Baudequin, C.; Brunet, J. J.; Rodriguez-Zubiri, M. Organometallic 2007, 26, 5264.
POSTERS
POSTERS
Poster 9
Poster 10
Transition Metal-Catalyzed Cyclization Reactions of Anthranyl Allenamides for the
New Homo Dimetallic-Salophen Complexes as Potential Receptors for Anionic and
Neutral Species in Organic Solvents
Synthesis of 2-Vinyl- and 2-(-Styryl)-quinazolin-4-ones
Michele Bruschini,a* Antonella Dalla Cort,a Luigi Mandolini,a Luca Schiaffinob
Elena Borsini,* Gianluigi Broggini, Andrea Fasana
a
Dipartimento di Scienze Chimiche e Ambientali, Università dell’Insubria, via Valleggio 11, 22100 Como, Italy
Dipartimento di Chimica, Sapienza Università di Roma, Piazzale Aldo Moro 5, 00185 Roma
b
Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi Tor Vergata, 00173 Roma
*[email protected]
*[email protected]
During the past three decades, allenes have been shown to be versatile intermediates in organic synthesis. [1] Among
Metal-salophen complexes are widely used in Supramolecular Chemistry, not only for their remarkable synthetic
them, allenamides were proven to be a versatile and effective building blocks to access nitrogen-containing heterocycles.[2]
In the present work we focused our attention towards the cyclization of N-Boc-protected anthranyl allenamides in the
presence of gold and palladium catalysts as a route to 2-vinyl- and 2-(-styryl)-quinazolin-4-one derivatives. Products
respectively arise from an intramolecular Au-catalyzed hydroamination process involving the internal C-C double bond and
a domino carbopalladation/5-exo-allylic amination of the allene moiety (Figure 1).
Boc
Boc
N
NH
Au catalyst
N
R'
R
O
hydroamination
R'
process
N
O
Pd catalyst
R
carboamination
R'
process
In the past few years, our attention has been focused on the design and synthesis of salophenic derivatives containing
zinc (Zn2+) and uranyl (UO22+) dications. These complexes have been successfully used as receptors for neutral and anionic
guests,[2] while the uranyl derivatives have found application in the catalysis of reactions such as Diels-Alder[3] and
Michael addition.[4] More recently, on the basis of previous results, we undertook the design of non-symmetric dinuclear
Boc
.
accessibility, but also for their properties as receptors and catalysts. [1]
metal-salophen complexes containing two different salophen-uranyl moieties. The aim is to test their binding properties
Ar
and obtain potential catalysts with hierarchical catalityc sites.
N
Here the synthesis of the dinuclear complexes 1,2 (Figure 1) and the results of prelimirary binding studies will be
N
shown.
R
O
C10H21O
Figure 1
N ON
U
O OO
N ON
U
O OO
OC10H21
These procedures represent more flexible alternatives to the synthesis of 2-vinyl-quinazolin-4-ones by direct
1
palladium-catalyzed amination of alkenes, already described in the literature, achievable only from N-tosyl-protected
anthranyl allylamides.
[3]
The Au-catalyzed hydroamination leads to the easy to handle N-Boc-protected 2-vinyl-quinazolin-
4-ones, while the Pd-catalyzed carboamination allows the formation of a different kind of the vinyl moiety.
C10H21O
N O N
U
O O O
NN
N
N ON
U
O O O
References
[1]
Krause, N.; Hashmi, A. S. K. Modern Allene Chemistry, Wiley-VCH: Weinheim, 2004.
[2]
(a) Wei, L.-L.; Xiong, H.; Hsung, R. P. Acc. Chem. Res. 2003, 36, 773; (b) Beccalli, E. M.; Bernasconi, A.; Borsini, E.; Broggini, G.;
2
Rigamonti, M.; Zecchi, G. J. Org. Chem. 2010, 75, 6923. (c) Hayashi, R.; Feltenberger, J. B.; Hsung, R. P. Org. Lett. 2010, 12, 1152. (d)
Figure 1
Standen, P. E.; Kimber, M. C. Curr. Opin. Drug Di. De. 2010, 13, 645.
[3]
Beccalli, E. M.; Broggini, G.; Paladino, G.; Penoni, A.; Zoni, C. J. Org. Chem. 2004, 69, 5627.
References
[1]
Dalla Cort, A.; De Bernardin, P.; Forte, G.; Yafteh Mihan, F. Chem. Soc. Rev., 2010, 39, 3863-3874.
[2]
Dalla Cort, A.; Mandolini, L.; Pasquini, C.; Rissanen, K; Russo, L.; Schiaffino, L. New J. Chem., 2007, 31, 1633-1638.
[3]
Dalla Cort, A.; Mandolini, L.; Schiaffino, L. Chem. Comm., 2005, 30, 3867-3869.
[4]
Dalla Cort, A.; Mandolini, L.; Schiaffino, L. J. Org. Chem., 2008, 73, 9439-9442.
OC10H21
Poster 11
Poster 12
Acetone vapours uptake and extrusion by a crystalline metallorganic
Design of new heterobifunctional linkers for the covalent binding of biomolecules onto
Ru(II) half-sandwich complex
Superparamagnetic Iron Oxide Nanoparticles (SPIONs)
Giulia Cantoni,a* Alessia Bacchi,a Mauro Carcelli,a Paolo Pelagatti,a
Claudio Carrara,* Andrea Pizzi, Silvia Sonzini, Emanuela Licandro
Dipartimento di Chimica G.I.A.F., Università di Parma, Viale G.P. Usberti 17/A, 43124 Parma, Italy,
Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, Via G. Venezian 21, 20133, Milano,
*[email protected]
*[email protected]
a
We are particularly interested in the rational design of non porous metallorganic networks, able to create receptor sites
in the crystal when exposed to the presence of suitable substrates.
Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are attractive because of some peculiar properties such as
selective separation of biomolecules and cells, automated DNA extraction, targeted gene delivery, use as magnetic
In this work we have engineered an host system based on the wheel-and-axle geometry, since this awkward molecular
resonance contrast agent (MRI), and magnetic field induced hyperthermia for cancer therapy. [1a-e] For application in
shape frustrates the achievement of a unique compact stable packing and therefore facilitates inclusion of small molecules
biomedicine, SPIONs must be coated with appropriate biomolecules by a stable and easily tunable adsorption. Hence, the
that fill the voids.[1]
need to develop efficient synthetic strategies for the synthesis of novel bio-nanoconjugates is an important and appealing
Here we have considered as wheels Ru(II)(p-cymene)X2 (X = Cl, I) units, while the spacer is a rigid supramolecular
target.[2] The strategies used to anchor molecules onto these nanoparticles can involve passive noncovalent adsorption on
axle, obtained by the dimerization of the carboxylic acid functions belonging to organic ligands, such as 4-amino-3-
the outer particle surface or the formation of a more stable covalent bond by using appropriate heterobifunctional linkers
hydroxybenzoic acid and 3-amino-4-hydroxybenzoic acid.
between SPION and the biomolecule, in which one functional group of the linker binds specifically the nanoparticle, while
Among the four wheel-and-axle metal-organic (WAAMO) complexes object of the present communication, [(p-
the other reacts with the biomolecule in order to form the new nanoconjugate (Figure 1).
cymene)Ru(3-amino-4-hydroxybenzoic acid)I2] was crystallized in two different forms: as a non-solvate from acetonitrile,
whose structure shows the expected packing, and as acetone-solvate from acetone where a molecule of such a solvent
In this poster, the discovery of a new functional group able to bind specifically the SPIONs is shown, leading to a new
class of heterobifunctional linkers for SPIONs functionalization.
interacts with the hydroxilic group of the ligand.
When the microcrystalline powder of the non solvate complex is exposed to acetone vapours its complete conversion
to the solvate form is observed within 1 hour at room temperature, with a strong color change from tan to black (Figure 1).
The acetone uptake and extrusion (induced by heating) have been monitored by X-ray powder diffraction, by which it has
been possible to verify that the solvation/desolvation processes occur with complete retention of crystallinity.
Figure 1
References
[1]
(a) H. Gu, K. Xu, C. Xu and B. Xu, Chem Commun., 2006, 941; (b) B. Yoza, A. Arakaki, K. Maruyama, H. Takeyama and T. Matsunaga,
J. Biosci. Bioeng., 2003, 95, 21; (c) M. Chorny, B. Polyak, I.S. Alferiev, K. Walsh, G. Friedman and R.J. Levy, FASEB J., 2007, 21,
2510; (d) M.G. Harisinghani, J. Barentsz, P.F. Hahn, W.M. Deserno, S. Tabatabaei, C.H. van de Kaa, J. de la Rosette and R. Weissleder,
N. Engl. J. Med., 2003, 348, 2491; (e) J.P. Fortin, C. Wilhelm, J. Servais, C. Menager, J.C. Bacri and F. Gazeau, J. Am. Chem. Soc., 2007,
129, 2628.
Figure 1
[2]
G. Prencipe, S. Maiorana, P. Verderio, M. Colombo, P. Fermo, E. Caneva, D. Prosperi and E. Licandro, Chem. Commun., 2009, 6017.
References
[1]
Bacchi, A.; Carcelli, M.; Chiodo, T.; Mezzadri, F. Cryst. Eng. Comm, 2008, 10, 1916.
POSTERS
POSTERS
Poster 13
Poster 14
How structural modifications can tune asymmetric cyclopropanations catalyzed by Cu(I)
Synthesis of new tetrathia[7]helicene-based gold(I) complexes
complexes of pyridine containing chiral macrocylcic ligands (Pc-L*)
Silvia Cauteruccio,a Davide Dova,a Annette Loos,b
A. Stephen K. Hashmi,b Emanuela Licandro,a Stefano Maioranaa
Brunilde Castano,* Emma Gallo, Alessandro Caselli
a
Department of Inorganic, Metallorganic and Analytical Chemistry, University of Milano, Via Venezian 21, 20133 Milan, Italy,
b
*[email protected]
Dipartimento di Chimica Organica e Industriale, Università di Milano, Via C. Golgi 19, 20133 Milano, Italia
Organisch-Chemisches Institut, Universitat Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
*[email protected]
We have recently reported that copper(I) complexes of the new C1-symmetric pyridine-based 12-membered tetraaza
Tetrathia[7]helicenes (7-TH) are polyconjugated -systems in which four thiophene rings are orthofused to alternating
macrocycles, Pyridine Containing Ligands (Pc-L*), are competent catalysts in the asymmetric cyclopropanation. [1] We
report here the synthesis of new C1- and C2-symmetric Pc-L* macrocycles and the use of their Cu(I) complexes as catalysts
arene rings to generate a non planar, chiral, stable helix which allows the existence of M and P enantiomers. The 7-TH
for the title reaction (scheme 1).
systems are very interesting structures[1] even because they can be easily and selectively functionalized in the alpha
positions of the terminal thiophene rings,[2] making it possible the introduction of appropriate substituents.
N
TsN
R
H2N *
2
N
OH
Cl
Cl
R
*
NTs
N
*
In the course of our studies on the synthesis of phosphane derivatives of 7-TH as potential innovative chiral ligands in
R
stereoselective organometallic catalysis, [3] novel gold(I) complexes of the mono and bidentate phosphine of 7,8-di-n-
* R'
Path A
4 TsCl
propyl-tetrathia[7]helicene have been synthesized (Scheme 1) and tested in some model carbon-carbon bond forming
R'
*
R
2
R'
NH2
*
* N
N Ts
R
* NHTs
R
* NHTs
reactions.
*
TsN
N
*
NTs
S
N
R = H, i-Pr
R' = H, CH3
Ts = tosyl
Path B
N
OMs
S
S
PPh2
* R'
OMs
X
R=H
Au(tht)Cl
X
S
S
tht :
AuCl
PPh2
CH2Cl2, r.t.
S
S
S
S
Scheme 1. Synthesis of the macrocyclic ligands
X : H, PPh2
The synthetic paths, reported in scheme 1, are very simple and they take advantage of commercially available,
X : H, PPh2
AuCl
enantiomerically pure, chiral amino-alcohols and/or primary amines. These last compounds can react either with 2,6Scheme 1
Bis(chloromethyl)pyridine (path A) or with the stereochemically pure forms of the alkyl pyridines obtained by the Lipase(path B). Ligands with different structures have been
The use of gold in homogeneous catalysis has witnessed tremendous activity in recent years. 4 In fact, thanks to gold(I)
obtained in moderate to good yields (40-80%) and they have been fully characterized. The Cu(I) complexes of those ligands
phosphine-based catalysts, various organic transformations have been accessible with both high yields and chemo- and
showed good catalytic activities in the cyclopropanation of differently substituted olefins employing ethyl diazoacetate
stereoselectivity.
catalyzed kinetic acetylation of 2,6-bis(1-hydroxyethyl)pyridine
[2]
(EDA) as carbene precursor. In all cases a complete conversion of EDA was observed and, depending on the employed
ligand, cyclopropanes were obtained with tunable cis/trans stereoselectivities and e.e. up to 96%.
References
[1]
Collins, S. K.; Vachon, M. P. Org. Biomol. Chem. 2006, 4, 2518.
References
[2]
Licandro, E.; Baldoli, C.; Maiorana, S. et al. Synthesis 2006, 3670.
[1]
Caselli, A.; Cesana, F.; Gallo, E.; Casati, N.; Macchi, P.; Sisti, M.; Celentano, G.; Cenini, S. Dalton Trans., 2008, 4202.
[3]
Cauteruccio, S.; Licandro, E.; Maiorana, S. et al. submitted for publication.
[2]
Uenishi, J.; Aburatani, S.; Takami, V. J. Org. Chem., 2007, 72, 132.
[4]
Hashmi, A. S. K.. Chem. Rev. 2007, 107, 3180.
Poster 16
Poster 15
Tetraferrocenylporphyrins as photosensitizers on ITO surfaces
Palladium nanoparticles for carbon-carbon cross-coupling reactions
under green conditions
Alessia Coletti,a* Valeria Conte,a Barbara Floris,a Pierluca Galloni,a Emanuela Gatto,a Victor Nemykin,b
Martina Tiravia,a Andrea Vecchi,a Mariano Venanzia
Francesca Coccia,* Lucia Tonucci, Mario Bressan, Nicola d’Alessandro
a
Department of Science, University “G. D’Annunzio” of Chieti and Pescara, Viale Pindaro 42, 65127 Pescara (PE), Italy
b
*[email protected]
Università degli Studi di Roma “Tor Vergata”, Via della Ricerca Scientifica, 00133 Roma, Italy
Department of Chemistry & Biochemistry, University of Minnesota-Duluth, Duluth, Minnesota 55812
*[email protected]
Palladium-catalyzed cross-coupling reactions of aryl halides for the formation of new carbon-carbon bonds have huge
Tetraferrocenylporphyrins (TFcP) are meso-substituted porphyrins which can form metal complexes with several
potential for use in fine organic synthesis, with particular emphasis on the pharmaceutical field. [1] Interest in their
metals, such as Zinc and Nickel. Since they have broad Soret and Q absorption bands and a low reduction potential,[1] we
applicability has grown over the years, with the award of the Nobel Prize to Prof. R. Heck, E. Negishi, and A. Suzuki. The
applied it as an electron donor in donor-acceptor dyads.[2] Following the interesting results obtained,2 the ITO surface was
focus of studies today is to make the experimental conditions more environmentally friendly [2] (e.g. in water and aerated
covered with TFcP monolayers in order to investigate the behavior of TFcP as photosensitizer in molecular photodevices.
solutions, at moderate temperatures, and in the presence of small amounts of catalyst). Free-ligand catalysts, like
The formation of the SAM was obtained through two different linkages: i) a covalent bond using a conveniently substituted
nanoparticles, can operate under conditions that are particularly green.[3] We therefore synthesized new palladium
TFcP (Figure 1a) and ii) a non-covalent bond, through the functionalization of the ITO surface with pyridine derivatives to
nanoparticles starting from PdCl2 and lignin,[4] the latter of which is a naturally abundant by-product from the paper
allow the formation of a metal-ligand bond between metal-porphyrin and pyridine functionalities (Figure 1b).
industry, which in our case was used as a stabilizing and reducing agent. These nanoparticles were fully characterized by
TEM (Figure 1), UV-Vis, XRD and IR techniques, and they catalyzed the Heck reaction between 4-iodophenol and styrene.
This led to the production of 4-hydroxystilbene, a potent tyrosinase inhibitor,[5] with 100% yield in water solution at 80 °C.
The same catalytic system was used for the Suzuki reaction, which obtained several substituted biphenyl derivatives. The
substrates that have been considered, the reaction yields, and the selectivities will be discussed further during the
presentation.
Figure 1
Figure 1: Heck reaction catalysed by Pd nanoparticles. Photograph: TEM image of Pd nanoparticles
Preliminary results with both systems will be discussed.
References
[1]
Shmidt, A. F.; Kurokhtina, A. A. Russian J. Appl. Chem. 2010, 83, 1248.
[2]
Na, Y.; Park, S.; Han, S. B.; Han, H.; Ko, S.; Chang, S. J. Am. Chem. Soc. 2004, 126, 250.
References
[3]
Han, W.; Liu, C.; Jin, Z. Adv. Synth. Catal. 2008, 350, 501.
[1]
[4]
Tonucci, L.; Coccia, F.; Bressan, M; d’Alessandro, N. ChemSusChem, submitted.
[5]
Ohguchi, K.;Tanakab, T.; Kidoc, T.; Babac, K.; Iinumad, M.; Matsumotoa, K.; Akaoa, Y.; Nozawa, Y. Biophys. Res. Commun. 2003,
Nemykin, V. N.; Rohde, G. T.; Barrett, C. D.; Hadt, R. G.; Bizzarri, C.; Galloni, P.; Floris, B.; Nowik, I.; Herber, R. H.; Marrani, A. G.;
Zanoni, R.; Loim, N. M. J. Am. Chem. Soc., 2009, 131, 14969.
[2]
Galloni, P.; Floris, B.; De Cola, L.; Cecchetto, E.; Williams, R. M.; J. Phys. Chem. C, 2007, 111, 1517.
307, 861.
POSTERS
POSTERS
Poster 17
Poster 18
Synthesis and properties of bis(polypyridyl)(BIAN)ruthenium(II) complexes for DNA
Lithiated 2-Phenyloxetane: A New Attractive Synton for the Preparation of
metallointercalation applications
Oxetane Derivatives
Andrew D. Phillips, Susan Quinn, Lenka Fujakova and Craig Connolly*
Donato Ivan Coppi,* Antonio Salomone, Filippo Maria Perna, and Vito Capriati
School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland,
Università di Bari “Aldo Moro”, Dipartimento Farmaco-Chimico, Consorzio Interuniversitario Nazionale Metodologie e Processi Innovativi di
*[email protected], [email protected]
Sintesi C. I. N. M. P. I. S., Via E. Orabona 4, I-70125 – Bari, Italy,
*[email protected]
Metal-based drugs continue to be a topic of intense investigation, especially with regards to binding biologically
relevant targets, including proteins, RNA and DNA. An entire class of bio-organometallic compounds now exists dedicated
Oxetanes, the closest homologs to epoxides, are an important group of four-membered cyclic ethers that, as equivalent
to strong DNA binding based on the bis-dipyridyl-ruthenium(II) fragment. A number of secondary supporting N,N’-
for the a3-synthon, can undergo a wide range of chemical transformation; their ring motif is also found in many natural
chelating ligands have been developed and explored, each with a specific characteristic for DNA binding, with major and
products that exhibit a range of biological activities.[1] The importance of oxetanes as versatile buiding blocks to synthetic
minor groove sites targeted.
and medicinal chemistry as well as to material and agrochemical sciences is dramatically increased over the last ten years
Now we present a new family of compounds based on the bis(aryl)acenaphthenequinonediimine, termed BIAN. This
with the development of new and efficient methods for their preparation.[2]
neutral ,-diimine features both flanking aryl groups and a naphthene group for base pair intercalation. Furthermore, we
Despite recent advances, their reactivity toward organometallic reagents has only been scarcely explored. Inspired by
have exploited the presence of the flanking aryl to incorporate para-substituted dimethylamino groups, NMe2, to impart
intensive interest in the field of -lithiated oxiranes[3] we became intrigued by the possibility of both generating an -
substantial aqueous solubility, for which this class of compounds is normally observed to be quite insoluble in water.
lithiated oxetane chemically stable on the timescale of its reactions and of investigating its reactivity. Herein, we report a
promising route to 2-substituted phenyloxetanes 2 exploiting the nucleophilic reactivity of -lithio-2-phenyloxetane 1-Li
Step 1
Step 2
R
R
R'
R'
R'
N
RuCl3.xH2O +
N
Ru
N
N
Cl
Cl
Ru
N
N
R'
Cl
Cl
+
N
N
N
N
R'
N
Ru
N
N
N
R'
R'
N
N
N
prepared by means of an hydrogen-lithium exchange from 2-phenyloxetane 1. Configurational stability of 1-Li on the time
scale of its reactions will also be tackled.
R'
R'
N
R'
.2Cl-
R
R
We herein present the detailed syntheses and comprehensive characterisation for a series of Ru(II)-BIAN complexes
featuring the 2,2’-dipyridyl, 4,4’-dimethyl-2,2’-dipyridyl and phenanthroline supporting ligands. Following some modest
success with thermal routes,[1,2] we now employ a microwave activated route for all steps [3] resulting in higher yields,
shorter reaction times and only trace formation of side products, specifically the corresponding tris-homoleptic Ru(II)
species. Moreover, bio-analytical results will be provided detailing the relative strength DNA binding in the series.
References
[1]
[1]
Sullivan, B. P.; Salmon, D. J.; Meyer, T. J. Inorg. Chem., 1978, 17, 3334.
[2]
[2]
Evans, I. P.; Spencer, A.; Wilkinson, G. J. Chem. Soc., Dalton Trans., 1973, 2, 204.
[3]
[3]
Rau, S.; Schäfer, B.; Grüßing, A.; Schebesta, S.; Lamm, K.; Vieth, J.; Helmar, G.; Walther, D.; Rudolph, M.; Grummt, U. W.; Birkner, E.
Inorg. Chim. Acta, 2004, 357, 4496.
Hailes, H. C.; Behrendt, J. M. in Comprehensive Heterocyclic Chemistry III; Oxetanes and Oxetenes: Monocyclic, Vol. 2 (Ed.: A. R.
Katritzky), Pergamon, Oxford, 2008, Chapter 2.05, p. 321.
References
Burkhard, J. A.; Wuitschik, G.; Rogers-Evans, M.; Müller, K.; Carreira, E. M. Angew. Chem. Int. Ed. 49, 2010, 9052.
(a) Capriati, V.; Florio, S.; Perna, F. M.; Salomone, A. Chem. Eur. J. 2010, 16, 9778. (b) Perna, F. M.; Salomone, A.; Dammacco, M.;
Florio, S.; Capriati V. Chem. Eur. J. 2011, DOI: 10.1002/chem.201100351.
Poster 19
Poster 20
Constrained bis(o-nitroaryl)aryl derivatives: synthesis by Suzuki-Miyaura coupling and
Silver Catalyzed Intramolecular Cyclization of 2-Alkynyl-acetophenones and
their transformation to carbazoles by nitrene insertion
2-Alkynyl-3-acetylpyridines in the Presence of Ammonia
Benedetta Cornelio,a,b* Marie Laronze-Cochard,b Antonella Fontana,a Janos Sapib
Monica Dell’Acqua,* Diego Facoetti, Giorgio Abbiati, Elisabetta Rossi
Dipartimento di Scienze del Farmaco, Università degli Studi “G. d’Annunzio”, Via dei Vestini 31, 66100, Chieti, Italy
DISMAB – Sezione di Chimica Organica “Alessandro Marchesini”, Università degli Studi di Milano, Via Venezian 21, 20133 Milano, Italy,
Laboratoire de Chimie Thérapeutique, UMR CNRS 6229, ICMR, Faculté de Pharmacie, Université de Reims Champagne-Ardenne, 51 Rue
*[email protected]
a
b
Cognacq Jay, 51096 Reims Cedex, France,
*[email protected]
Recent work of our laboratory
[1]
The development of new domino approaches for the synthesis of nitrogen containing heterocycles is a research field
has evidenced that carbazoles 2 can be obtained from bis(o-nitrophenyl)aryl
derivatives 1 by N-heteroannulation via an Pd/C catalyzed hydrogenation reaction.
in continuous evolution. In particular, for many years we have been interested in the synthesis of nitrogen containing rings
starting from alkyne derivatives[1] in the presence of ammonia.
Recently we reported a valuable approaches to the synthesis isoquinolines starting from 2-alkynyl-benzaldehydes,[2]
and the approach was also successfully transformed in a multicomponent process. [3] Unexpectedly, when we tried to react
2-alkynylacetophenone derivatives under optimized conditions the reaction failed. This result prompt us to investigate the
reaction of alkynyl ketones more in depth. We started our study looking for the best conditions to trigger the domino
reaction on a model compound. We tried some metal catalysts potentially able to promote both the imine formation as
Lewis acid, and the intermolecular hydroamination step as alkynophilic catalysts. [4] We were delighted to find that the
metal catalysed reaction gave the desired isoquinoline, beside variable amounts of the isomeric naphthalen-1-amine. The
In order to study the mechanism and the structural requirements of the generation and the insertion of a possible nitrene
best results were obtained with AgOTf in terms of conversion, selectivity and reaction times.
Scope and limitation of the approach have been extensively studied. We found that the silver-catalyzed/microwave-
species, we devised diverse constrained bis(o-nitroaryl)aryl derivatives 4 as simplified models of 1.
Compounds
4
were
synthesized
by
Suzuki-Miyaura
cross-coupling
reaction
between
o-bromonitrobenzene 5 and various o-substituted phenylboronic acids 6. Pd nanoparticles have been used for the cross-
promoted domino imination/annulation of alkynes bearing a proximate carbonyl group in the presence of ammonia is an
interesting alternative for the synthesis of aromatic heterocycles and carbocycles. A plausible mechanism is also suggested.
CH3
coupling reaction and compared to the classical Suzuki catalyst Pd(PPh3)4.
R1
AgOTf (10% mol)
O
NH 3/MeOH
X
2
R
CH3
R1
N
X
NH 2
R1
+
R2
X
R2
120 °C,  W
X = CH, N
R 1 = H, MeO, F
R 2 = Ar, Alk, SiMe3
20 examples
Results of the comparative study of the experimental conditions (Pd/C-H2 vs. P(OEt)3) used for the preparation of 3 from 4
References
will be reported.
[1]
For some recent representative examples see: (a) Dell'Acqua, M.; Facoetti, D.; Abbiati, G.; Rossi E. Tetrahedron 2011, 67, 1552. (b)
Dell'Acqua, M.; Facoetti, D.; Abbiati, G.; Rossi E. Synthesis 2010, 2367. (c) Facoetti, D.; Abbiati, G.; d’Avolio, L.; Ackermann, L.;
Acknowledgements Financial supports from Région Champagne-Ardenne and UE (Fonds FEDER) are gratefully acknowledged.
Rossi E. Synlett 2009, 2273.
References
[2]
Alfonsi, M.; Dell’Acqua, M.; Facoetti, D.; Arcadi, A.; Abbiati, G.; Rossi, E. Eur. J. Org. Chem. 2009, 2852.
[1]
Laronze-Cochard, M.; Cochard, F.; Daras, E.; Lansiaux, A.; Brassart, B.; Vanquelef, E.; Prost, E.; Nuzillard, J.-M.; Baldeyrou, B.;
[3]
Dell’Acqua, M.; Facoetti, D.; Arcadi, A.; Abbiati, G.; Rossi, E. Synlett 2010, 2672.
Goosens, J.-F.; Lozach, O.; Meijer, L.; Riou, J.-F.; Henon, E.; Sapi, J. Org. Biomol. Chem., 2010, 8, 4625.
[4]
For a recent review on - and -electrophilic Lewis acids see: Yamamoto, Y. J. Org. Chem 2007, 72, 7817.
POSTERS
POSTERS
Poster 21
Poster 22
Synthesis of Sulfonated Supported Hydrogen-Bonding NHC-Catalysts
Supramolecular bisoxazolines for asymmetric acylations
Ruben Drost,* Cornelis Elsevier
Marco Durini,a,b* Oliver Reiser,b Umberto Piarulli,a
Van’t Hoff institute for molecular sciences, University of Amsterdam, Sciencepark 904 Postbus 94270 1090 GD Amsterdam, The Netherlands,
a
b
*[email protected], website: www.science.uva.nl/research/molinc/
Department of Chemical Science, University of Insubria, Como, Italy, [email protected]
Institute of Organic Chemistry, University of Regensburg, Germany, [email protected]
*[email protected]
The importance and use of catalysis as well as the need for recycling of transition-metal catalysts is stressed
Self-assembly of complementary species through hydrogen bonding is a widely occurring phenomenon in nature, as
abundantly. One method for recycling is attachment of homogeneous catalysts to a support. This combines the rational
design and the high activity and selectivity of homogeneous catalysts with the facile recycling and stability of a
exemplified by DNA base pairing and the secondary or tertiary structure of proteins. The concept of self-assembly of
bidentate ligands through hydrogen bonding for combinatorial homogeneous catalysis was recently introduced, and several
heterogeneous catalyst[1].
One method for heterogenization is Supported Hydrogen-bonding. Through a non-covalent interaction of a sulfonate
with the silanol groups in silica a catalyst is supported. This non-covalent attachment allows synthesis of the material
powerful ligands were described with outstanding reactivity and selectivity. [1] Unfortunately, this methodology has thus far
been largely confined to the use of phosphorus ligands.
We report herein the first example of H-bond induced assembly of monodentate oxazolines for the formation of
through a simple and reversible adsorption. NHC catalysts, such as 1 are investigated as Supported Aqueous Phase Catalyst
(SAPC) (figure 1) , NHC complexes are often air and water stable, show high activities and little to no ligand
supramolecular bisoxazoline metal complexes, and application of the resulting complexes in catalytic asymmetric
dissociation[3], which makes them ideal for this type of catalysis.
transformations. In particular, the self-assembling was achieved via two additional urea groups as hydrogen bond donors
[2]
and acceptors.[2]
The ligands were obtained starting from several scaffolds containing a carboxylic acid and an amino functionalities
which were transformed into the corresponding ureas by reaction with different isocyanates and oxazolines by coupling to
different amino alcohols followed by cyclization. The formation of the Pd 2+ and Cu2+ complexes was investigated by 1HNMR, HR-MS and Job’s method of continuous variations.
Preliminary results in the enantioselective acylation of diols show a good potential for this approach; moreover this
Figure 1: SAPC with a sulfonated NHC catalyst.
catalytic systems are selective also using meso substrates with quantitative yields and enantiomeric excesses up to 88%.
References
[1]
Coperet, C.; Chabanas, M.; Saint-Arroman, R. P.; Basset, J. M. Angew. Chem. Int. Ed. 2003, 42, 156.
References
[2]
Horn, J.; Michalek, F.; Tzschucke, C. C.; Bannwarth, W. in Immobilized Catalysts, Vol. 242, Springer-Verlag Berlin, Berlin, 2004, pp. 43.
[1]
Sandee, A. J.; van der Burg, A. M.; Reek, J. N. H. Chem. Commun., 2007, 864.
[3]
Hahn, F. E.; Jahnke, M. C. Angew. Chem. Int. Ed. 2008, 47, 3122.
[2]
Carboni, S.; Gennari, C.; Pignataro, L.; Piarulli, U. Dalton Trans., 2011, 40, 4355.
Poster 23
Poster 24
A thermomorphic catalytic system based on non-fluorous phase-tagged phenanthrolines
Towards new ligands for metal complexation and catalysis
and palladium for the synthesis of carbamates from nitroarenes
B. Gjoka,* F. Romano, M. Mba, C. Zonta*, G. Licini
Francesco Ferretti,* Fabio Ragaini
Università di Padova, Dipartimento di Scienze Chimiche, Via Marzolo 1, 35131, Padova, Italy
*[email protected]
Dipartimento di Chimica Inorganica, Metallorganica e Analitica “L. Malatesta”, Università di Milano, Via Venezian 21, Milano, Italy,
*[email protected]
Recently, we developed an efficient synthesis of triphenolamine 1.
The synthesis of carbamate from nitroarene is one of the most promising strategies for the elimination of phosgene in
the synthesis of isocyanates (eq.1).
wide variety of transition and main group elements
[2]
such as Ti(IV),
[3]
[1]
They can form stable metal complexes with a
V(V)[4] and Mo(VI)[5] which achieved noteworthy
catalytic properties in the oxidations of sulfides, secondary amines, halides and olefines. As an extension of our work, we
examined the use of their analougues tri-thiofenolamino systems. It is known that many metallo-enzymes contain
(1)
In our laboratories we developed the most active catalytic system for this reaction, based on the use of palladium and
phenanthroline complexes in the presence of phosphorus acids.
[1, 2]
One of the main problems in these homogeneous
systems is the recovery and recycle of the catalyst that limits a possible industrial application. Thermomorphic catalysts are
an interesting alternative to the “classical” immobilization of the catalyst into polymeric matrices because they allow to run
molybdenum atom centers coordinated to sulfur atoms. Key step for the introduction of sulfur atom is the Newmann-Kwart
rearrangement, which is a valuable synthetic technique to convert phenols in thiophenols. Herein we will report the
synthetic strategy for the preparation of the new parent compound 2 and their coordination chemistry with
transition metals such as molybdenum (Mo) or vanadium (V).
the reaction in an homogeneous environment and subsequently recover the catalyst in a separate phase as a consequence of a
temperature change.[3]
Here we report the synthesis and the application as ligands in the palladium catalyzed carbonylation of nitrobenzene of
some phenanthrolines substituted with long alkyl chains as phase-tags. We investigated catalyst recovery using both
liquid/solid (A) and liquid/liquid (B) separation strategies.
Acknowledgements We acknowledge financial support from MIUR, PRIN 2008 project, University of Padova, Cariparo and COST ACTION D40
‘Innovative Catalysis – New Processes and Selectivities.
References
Figure 1
References
[1]
Ragaini, F. Dalton Trans. 2009, 6251.
[2]
Ragaini, F.; Gasperini, M.; Cenini, S. Adv. Synth. Catal. 2004, 346, 63.
[3]
Bergbreiter, D. E. in Recoverable and Recyclable Catalysts (Ed.: M. Benaglia), John Wiley & Sons, Ltd, 2009, pp. 117-153.
[1]
Prins, J L.; Mba, M.; Kolarović, A.; Licini, G. Tetrahedron Letters. 2006, 47, 2735..
[2]
Licini, G.; Mba, M.; Zonta, C. Dalton Trans. 2009, 27, 5265..
[3]
(a) Mba, M.; Prins, L. J.; Licini, G. Org. Lett. 2007, 9, 15. (b) Zonta, C.; Cazzola, E. ; Mba, M.; Licini, G. Adv. Synth. Catal. 2008, 350,
2503. (c) Mba, M.;, Prins, L.J.; Zonta, C.; Cametti, M,; Valkonen, A.; Rissanen, K.; Licini, G. Dalton Trans. 2010, 39, 7384.
[4]
Mba, M.; Pontini, M.; Lovat, S.; Zonta, C.; Bernardinelli, G.; Kündig, E. P.; Licini, G. Inorg. Chem. 2008, 47, 8616.
[5]
Romano, F.; Linden, A.; Mba, M.; Zonta, C. Licini, G. Adv. Synth. Catal. 2010, 352, 2937.
POSTERS
POSTERS
Poster 25
Poster 26
The conversion of platform chemicals from biomass: multiphase
Syntheses, characterizations and crystal structures of new organotin complexes
hydrogenation/dehydration of levulinic acid to -valerolactone (GVL)
with (N-phenyl-2-indazolyl-1-carboximidothioate)
Marina Gottardo,* Alvise Perosa, Maurizio Selva
Moayad Hossaini Sadr,a Zahra Khalili Zadeh,a Behzad Soltania
Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari, Venezia, Italy; Dorsoduro 2137 - 30123 Venezia, Italy;
a
Department of Chemistry, Azarbaijan University of Tarbiat Moallem, Tabriz, Iran,
*[email protected]
*[email protected]
Levulinic acid (LA) can be cheaply produced from lignocellulosic materials via biological or chemical conversions,
The novel organometallic complexes of Sn(IV) have been synthesized by using new bidentate N,S-donor ligands of
and thanks to its dual functionality, LA is a precursor for a variety of useful intermediates in both pharma and food
the type PhNCSL (where L = indazole, pyrazole) and corresponding Ph3SnCl, Ph2SnCl2 or Bu2SnCl2 salts. The synthesized
sectors.[1] Not by chance, the US Department of Energy has recently classified LA among the twelve most attractive
compounds
biobased-chemicals.[2]
[Ph3Sn(PhNCSIndz)2] (Indz = indazole) was determined by X-ray diffraction analysis, showing a five-coordinate trigonal
In this study, an innovative method is reported for the catalytic hydrogenation/dehydration of levulinic acid to valerolactone (GVL). The reaction has been investigated under multiphase conditions, by using a 5% Ru/C catalyst,
were
characterized
by
common
spectroscopic
and
analytical
methods.
Crystal
structure
of
bipyramidal geometry (Figure 1). The space group of complex is P43, with a = 10.5305(3), b = 10.5305(3) Å, c =
25.5241(6) Å, α = β = γ = 90.00˚.
gaseous H2, and a liquid triphase system made by an hydrocarbon (isooctane), water and a catalyst-philic ionic liquid
(Scheme 1).
H2
O
OH
O
OH
O
OH
O
-Hydroxyvaleric acid
O
H2O
-Valerolactone (GVL)
Scheme 1
Notwithstanding its complexity, operating at 100°C and 35atm of H2, this arrangement not only allows substantially
quantitative yields of GVL, but it greatly improves the separation of the product and the recycle of the catalyst. Water acts
as a solvent for both the substrate (LA) and the product (GVL); while, the combination of the ionic liquid [especially,
trioctylmethylphosphonium bis(trifluoromethane)sulfonimide)] which strongly adsorbs over the catalytic (C) support, and
isooctane allow a perfect confinement of Ru/C between the hydrocarbon-water phases.
Figure 1
References
[1]
(a) Bozell, J. J.; Moens, L.; Elliott, D.C.; Wang, Y.; Neuenscwander, G. G.; Fitzpatrick, S. W.; Bilski, R. J. and Jarnefeld, J. L.;
Resources, Conservation and Recycling, 2000, 28, 227–239; (b) Horvath, I. T.; Mehdi, H.; Fabos, V.; Boda, L. and Mika, T. L.; Green
Chem., 2008, 10, 238-242.
[2]
Werpy, T. and Petersen, G. in Top Value Added Chemicals From Biomass, the Pacific Northwest National Laboratory
(PNNL) and the National Renewable Energy Laboratory (NREL), U.S. Department of Energy, 2004.
References
[1]
Hossaini Sadr, M.; Jalili, A.R.; Razmi, H.; Weng, Ng.S. J. Organomet. Chem. 2005, 690, 2128.
[2]
Hossaini Sadr, M.; Jahanbin Sardroodi, J.; Shagagia, Z.; Weng, Ng. S. Acta Cryst. 2005, E61, m1955.
[3]
Hossaini Sadr,M.; Khalilizadeh, Z.; Edward R. T.; Tiekink, M. Acta Cryst. 2007, E63, 04126.
[4]
Sakamoto, T.; Cullen, M. D.; Hartman, T. L.; Watson, K. M.; Buckeit, R. W.; Pannecouque, Ch.; Clereq, E.; Cushman, M. J. Med. Chem.
2007, 50, 3314.
Poster 27
Poster 28
Synthesis and characterization of copper(II) complexes incorporating novel
Mechanistic Insight Into The Allylic Amination Of Olefins Mediated by
pyrazolyl-derived N,S-donor bidentate ligands
Ru(Porphyrin)CO Complexes
Daniela Intrieri,* Alessandro Caselli, Fabio Ragaini, Emma Gallo
M. Hossaini Sadr,*a B. Soltani,a A. Jalili,a F. Nejadghafar,a J. T. Engle,b Ch. J. Zieglerb
a
Department of Inorganic, Metallorganic and Analytical Chemistry, University of Milano, Via Venezian 21, 20133 Milan, Italy,
Department of Chemistry, Azarbaijan University of Tarbiat Moallem, Tabriz, Iran,
*[email protected]
b
Department of Chemistry, University of Akron, Akron, OH, USA
*[email protected]
The biological and pharmaceutical activities of organonitrogen compounds prompted the scientific community to
-
-
The novel N,S-donor bidentate anionic ligands [PhNCSIndz] , 1, [PhNCSImz] , 2, [PhNCSPz
Me3 -
-
] , 3 and [EtNCSPz] ,
4; where Indz = indazole, Imz = imidazole, PzMe3 = 3,4,5-trimethylpyrazole and Pz = pyrazole, were synthesized and used
to prepare new copper(II) complexes of general formula [Cu(N^S)2]. The ligands 1–4 were synthesized via direct addition
develop new methods for the direct and selective C-N bond formation. The choice of the appropriate nitrogen source, to
introduce into the organic frameworks an aza-functionality, represents a key point to synthesise useful fine chemicals in an
economical fashion and using environmentally benign technologies.
We have focused our interest on amination reactions for several years using aryl azides as nitrogen sources and metallo
of phenylisothiocyanide or ethylisothiocyanide into the THF suspensions of corresponding sodium-pyrazolate salts. The
synthesized compounds were characterized by common spectroscopic and analytical methods. Crystal structures of
[Cu(EtNCSPz)2], 8, and [Cu(PhNCSPzMe2)2, 9, were determined by X-ray diffraction analysis, showing a trans-square
porphyrins as catalysts.[1] More recently, we have investigated the catalytic activity of Ru(TPP)CO in C-H bonds aminations
and we have isolated and characterised the active bis-imido intermediate Ru(TPP)(NAr)2 (Ar = 3,5-(CF3)2C6H3) (1).[2] To
propose a general mechanism for the reaction we have investigated the reactivity of Ru(TPP)CO (2) towards several aryl
azides, discovering that the nature of the active intermediate strongly depends on the electronic nature of the employed
azide. The replacement of 3,5-(CF3)2C6H3N3 with 4-CF3C6H4N3 in the reaction with Ru(TPP)CO allowed the isolation of the
mono-imido complex Ru(TPP)(NAr)CO (Ar = 4-(CF3)2C6H4) (3) that showed a good catalytic activity in hydrocarbon
aminations. On the other hand, the reaction of Ru(TPP)CO with an aryl azide bearing an electron donating group, 4t
BuC6H4N3, gave a very unstable imido complex (4). Complex 4 has been detected by NMR and it rapidly decomposed to
the mono-amino compound Ru(TPP)(NH2Ar)CO (Ar = 4-tBuC6H4) (5) that was isolated and characterised.
NAr
Ru
8
NAr
(1)
9
NAr
2 ArN3
-2 N2
Ru
CO
(2)
ArN3
-N2
Ru
CO
(3 or 4)
if
Ar = 4-tBuC6H4
H
NH2Ar
Ru
CO
(5)
planar geometry for 8 and a distorted tetrahedral geometry for 9 (Figure 1).
Figure 1
Figure 1
A kinetic investigation has been also performed to better rationalise the dependence of the reaction mechanism on the
nature of the organic azide.
References
[1]
Hossaini Sadr, M.; Jalili, A.R.; Razmi, H.; Weng Ng.S. J. Organomet. Chem. 2005, 690, 2128.
[2]
Hossaini Sadr, M.; Jahanbin Sardroodi, J.; Shagagia, Z.; Weng, Ng. S. Acta Cryst. 2005, E61, m1955.
[3]
Pettinari,C.; Santini,C.; Comprehensive Coordination Chemistry II, 2003, 1, Ch.1.10, 159.
References
[1]
(a) Cenini, S.; Gallo, E.; Caselli, A.; Ragaini, F.; Fantauzzi, S.; Piangiolino, C. Coord. Chem. Rev., 2006, 250, 1234; (b) Fantauzzi, S.;
Caselli, A.; Gallo, E. Dalton Trans., 2009, 5434.
[2]
Fantauzzi, S.; Gallo, E.; Caselli, A.; Ragaini, F.; Casati, N.; Macchi, P.; Cenini, S. Chem. Commun., 2009, 3952; (b) Intrieri, D.; Caselli,
A.; Ragaini, F.; Cenini, S.; Gallo, E. J. Porph. Phthal., 2010, 14, 732.
POSTERS
POSTERS
Poster 29
Poster 30
Synthesis of N-heterofunctionalized imidazolium salts
Synthesis of chiral platinum complexes and applications
and their reactivity towards Iridium(I)
to enantioselective enyne cycloisomerisations
Martin Jagenbrein,* Pierre Braunstein
Hélène Jullien,* Delphine Brissy, Rémy Sylvain, Angela Marinetti
Laboratoire de Chimie de Coordination, Institut de Chimie (UMR 7177 CNRS),
ICSN-CNRS, 1 avenue de la Terrasse, 91190 Gif-sur-Yvette,
Université de Strasbourg, 4 Rue Blaise Pascal, 67081 Strasbourg, France,
*[email protected]
*[email protected]
Enyne cycloisomerisations catalysed by transition metals represent powerful synthetic tools for the construction of
N-heterocyclic carbenes (NHCs) have gathered widespread attention as robust and strong donor ligands in transition
cyclic and heterocyclic moieties.[1] Asymmetric versions of these reactions remain rare.
metal chemistry. [1] The effort to generate different substitution patterns on the five-membered ring system of imidazoles
In our group, a new series of platinum (II) complexes have been designed as suitable catalysts for these reactions.
and imidazolines has triggered the syntheses of numerous derivatives. With regard to eventual catalytic applications of
They are square-planar platinacycles that combine a N-heterocyclic carbene and a chiral monodentate phosphine. These
their transition metal complexes, NHCs with heterofunctionalized NNHC-substituents exhibiting potentially hemilabile
complexes have been used successfully in the enantioselective cycloisomerisation of nitrogen tethered 1,6-enynes into 3-
character[2] have stimulated extensive research in the area.[3]
In the present work, the syntheses of a series of imidazolium salts as NHC precursors bearing potentially hemilabile
aza-bicyclo[4.1.0]hept-4-enes. Enantiomeric excesses of over 90% have been obtained when using (S)-Ph-Binepine as the
chiral phosphorus ligand, but MonoPhos type ligands also afforded significant levels of enantioselectivity. [2]
substituents of the type -OR, -SR, and -NR2 (R = Me, Et, Ph), are described. Thereby, the syntheses rely on known
literature methodology or novel routes to introduce the heterofunctionalized substituents. Notable variations comprise the
substitution pattern of the heterofunctionalized moieties leading to different stereoelectronic features of the potentially
hemilabile moiety (notably alkyl- vs. aryl-substituents). In addition, the bulkiness of the substituent of the second ring
nitrogen is altered.
ee up to 96%
The coordination behavior of the corresponding carbene species obtained via in situ deprotonation of the 1,3disubstituted imidazolium salts through excess CsCO3 towards Ir(I) was studied. The studies examined the nucleophilicity
of the heteroatoms as a function of the type of substituent (alkyl- to aryl). The coordination reactions were carried out
[Pt]*=
under remarkably mild conditions (room temperature) and completed within 24 hours. The resulting Ir(I)-NHC complexes
or
were stable in air and characterized via NMR spectroscopy and single crystal X-ray diffraction.
(S)-Ph-Binepine
References
(R)-Monophos
[1]
Jacobsen, H.; Correa, A.; Poater, A.; Costabile, C.; Cavallo, L. Coord. Chem. Rev. 2009, 253, 687.
[2]
(a) Braunstein, P. J. Organomet. Chem. 2004, 689, 3953; (b) Braunstein, P.; Naud, F. Angew. Chem., Int. Ed. 2001, 40, 680.
[3]
(a) Bierenstiel, M.; Cross, E.D. Coord. Chem. Rev. 2011, 255, 57; (b) Lee, H.M.; Lee, C.-C.; Cheng, P.-Y. Curr. Org. Chem. 2007, 11,
has been postulated. We will report here on the design and structural tuning of these platinum catalysts, as well as
1491.
extension of the catalytic process to new substrates.
A plausible stereochemical pathway for the enantioselective cycloisomerisation promoted by these Pt(II) complexes
References
[1]
Fürstner, A., Chem. Soc. Rev. 2009, 38, 3208.
[2]
(a) Brissy, D., Skander, M., Jullien, H., Retailleau, P., Marinetti, A. Org. Lett. 2009, 11, 2137. (b) Jullien, H., Brissy, D., Sylvain, R.,
Retailleau, P., Naubron, J.V., Gladiali, S., Marinetti, A. Adv. Synth. Cat. 2011, 353, 1109.
Poster 31
Poster 32
Synthesis and catalytic activity of rhodium(I) complexes with
New bicarboxylate-bridged Coordination Polymers (CPs) from CuII-pyrazolate
diphenylphosphinoferrocenyl thioether ligands
trinuclear clusters
Ekaterina M. Kozinets,a,b* Oleksandr Koniev,a Oleg A. Filippov,b Jean-Claude Daran,a
Enrico Forlin,a Federica Garau,a Arianna Lanza,a* Magda Monari,b Fabrizio Nestola,c
Rinaldo Poli,a,c Elena S. Shubina,b Natalia V. Belkova,b* and Eric Manourya
Luciano Pandolfo,a Claudio Pettinari,d Alberto Zorzia
a
b
a
CNRS; LCC; Université de Toulouse; UPS, INP; 205, route de Narbonne, F-31077 Toulouse, France
Dept. of Chemical Sciences, Univ. of Padova, Padova, Italy; bDept. of Chemistry, “G. Ciamician”, Univ. of Bologna, Bologna, Italy; cDept. of
Geosciences, Univ. of Padova, Italy, dSchool of Pharmacy, Univ. of Camerino, Italy,
A. N. Nesmeyanov Institute of Organoelement Compounds, RAS, Vavilov Street 28, 119991 Moscow, Russia,
c
*[email protected]
Institut Universitaire de France, 103, bd Saint-Michel, 75005 Paris, France,
*[email protected]
The synthesis and characterization of Coordination Polymers (CPs) is a new, quickly developing aspect of the general
Iridium complexes with diphenylphosphinoferrocenyl thioether ligands (1) (R = tBu, Et, Ph, Bz) are effective catalysts
field of coordination chemistry. The choice among many different metallic nodes and the infinite availability of organic di-
for ketone asymmetric hydrogenation.[1] With the aim of studying the reaction mechanism, we have prepared rhodium
and polytopic ligands make it possible to design and obtain a wide variety of new compounds with polymeric structures.
analogues by the reaction of P,S-ligands (1) with [Rh(NBD)Cl]2, [Rh(COD)Cl]2 and [Rh(COD)2]BF4. The new rhodium
This class of hybrid compounds often shows catalytic activity and, compared to the currently used catalysts, has the
chloro complexes 2 and 3 and the BF4- salts 4 have been obtained (Scheme 1), whereas the cationic NBD rhodium
potential advantage of possibly tuning the desired properties by tailoring and functionalizing the structure. 1 The reaction of
complexes 5 were obtained from the corresponding chlorides by the reaction with NaBF4 (Scheme 2).
CuII monocarboxylates with pyrazole (Hpz) leads to the formation of a huge variety of CPs featuring the triangular
[Rh(COD)Cl]2 +
[Rh(NBD)Cl]2 +
Fe
CH2SR
[Rh(COD)2]BF+4
trinuclear CuII moiety [Cu3(μ3-OH)(μ-pz)3]2+, which often self-assembles into supramolecular structures, generally through
yield 64%
carboxylate-bridges and/or hydrogen bonds (Figure 1). 2 The use of ditopic anionic linkers such as bicarboxylates could
yield 97-99%
allow the formation of new CPs in which the trinuclear “clusters” are connected by bicarboxylate bridges, whose
yield 42-99%
backbones can differ in length, geometry and flexibility.
Scheme 1
PPh2
1
2 RhCl(COD)(P,SR)
2
2 RhCl(NBD)(P,SR)
3
[Rh(COD)(P,SR)]BF4
4
2 (P,SR)
1
2 (P,SR)
1
(P,SR)
1
RhCl(NBD)(P,SR) + NaBF4
in CH2Cl2
in H2O
3
[Rh(NBD)(P,SR)]BF+4 Na Cl
in CH2Cl2
in H2O
5
yield 98-99%
Scheme 2
The structure of these complexes was determined by single crystal X-ray diffraction (for 4 with R = Ph, Bz) and by 1H,
13
C and
31
P NMR and IR spectroscopy in combination with DFT/B3LYP calculations. Their activity in catalytic ketones
hydrogenation was shown being similar to that of the Ir analogues but features an induction period in agreement with the
literature data on the asymmetric hydrogenation of prochiral olefins.[2] The hydrogenation of the precatalytic species under
stoichio-metric conditions in iPrOH and iPrOH/CH2Cl2 was monitored by UV/Vis spectroscopy. Catalytic studies show that
the hydrogenation with the COD rhodium complexes is slower than with the NBD complexes. The reactions with the
cationic complexes were faster than with the chloro complexes.
Figure 1
Acknowledgment We thank the CNRS and the RFBR for support through a France-Russia (RFBR-CNRS) bilateral grant No. 08-03-92506, the
GDRI “Homogeneous Catalysis for Sustainable Development”, and the French Embassy in Moscow for the financial support of joint PhD thesis
for EMK.
have been obtained and characterized by means of single crystal XRD determinations.
References
References
[1]
Le Roux, E.; Malacea, R.; Manoury, E.; Poli, R.; Gonsalvi, L.; Peruzzini, M., Adv. Synth. Catal., 2007, 349, 1064.
[2]
Preetz, A.; Drexler, H.-J.; Fischer, C.; Dai, Z.; Borner, A.; Baumann, W.; Spannenberg, A.; Thede, R.; Heller, D. Chem. Eur. J., 2008, 14,
1445.
Numerous CuII bicarboxylates have been reacted with Hpz in different condition (ambient and solvothermal) and new CPs
[1]
For recent accounts on CPs see the Special Issue of Chem. Soc. Rev. 2009, 38, 1201.
[2]
(a) Casarin, M. et al. Inorg. Chem. 2004, 43, 5865; (b) Casarin, M. et al. Inorg. Chem. 2005, 44, 6265; (c) Di Nicola, C. et al. Inorg.
Chem. 2007, 46, 221; (d) Contaldi, S. et al Dalton Trans., 2009, 4928; (e) Di Nicola, C. et al. Eur. J. Inorg. Chem., 2009, 666. (f)
Pettinari, C. et al. Chem. Eur. J. 2010, 16, 1106. (g) Di Nicola, C. Cryst. Growth Des. 2010, 10, 3120.
POSTERS
POSTERS
Poster 33
Poster 34
Naplephos and elpaNphos: tailored chiral ligands with improved functions
Mass Spectrometric Studies of Ruthenium(II) Complexes Used in DSSCs
Matteo Lega,* Francesco Ruffo
Camilla Lelii,a,b* Stefano Chiaberge,a Paolo Biagini,a Silvia Spera,a
Francesco De Angelis,b Marcello Crucianellib
Dipartimento di Chimica “Paolo Corradini”, Università di Napoli “Federico II”, Consorzio Interuniv. di Reattività Chimica e Catalisi, Italy,
*[email protected]
a
Eni S.p.A. Centro Ricerche per le Energie non Convenzionali, Ist. Eni Donegani, via Fauser 4, I-28100 Novara, Italy
b
Dipartimento di Chimica, Università degli Studi dell’Aquila, Via Vetoio, I-67100, L’Aquila, Italy
Homogeneous enantioselective catalysis is central for the production of fine chemicals. [1] In this field, innovative metal
*[email protected]
catalysts can be rationally prepared by selecting building blocks from the chiral pool. Within this frame, we have prepared
two pseudo-enantiomeric libraries of ligands (Naplephos and elpaNphos) based on D-glucose (Figure 1). This action aims to
Bipyridine ruthenium(II) complexes have been widely studied in recent years, and in particular they have been
furnish a complete scenario, in order to perform the same catalytic processes but with the production of the chiral products
employed as photosensitive dyes in dye sensitized solar cells (DSSC). [1] Their analytical characterization is routinely done
in opposite configuration.
by NMR spectroscopy, matrix assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) mass
spectrometry. [2] In this work we report on mass spectrometric studies on commercially available dyes, in order to set up an
phase tag
phase tag O
O
O
R
efficient and reliable analytical tool for the structure characterization of such compounds. To this goal, we have compared
O
O HN
the results obtained by conventional ESI and atmospheric pressure photoionization (APPI) [3] techniques, both coupled with
O
O
OR'
O
phase tag
O
O
O
Fourier trasform ion cyclotron resonance mass spectrometry (FTICR-MS). We found that the latter
O
ion source is
X HN
R
P
naplephos Ph Ph
elpanphos
particularly efficient for ionization of Ruthenium clusters, and can be applied also for neutral compounds with low polarity
P
Ph Ph
ligands, whereas the ESI technique requires chemical derivatization. [4] In addition, the high resolution (RP>400k) and the
high mass accuracy of the FTICR instrument allow to obtain the molecular formula assessment of all the peaks recorded in
the mass spectra (Figure 1).
Figure 1
Based on the relative orientations of the glucose chair, this approach has been pursued by introducing the same
essential coordinating motifs, respectively in positions 2, 3 (Naplephos) and 1, 2 (elpaNphos). Furthermore, the
multifunctional nature of the carbohydrate scaffold has been fully employed for a precise tailoring of the ligands, by
introducing appropriate phase-tags in the other ring positions. As an example, the following chelates were prepared,[2] which
show polar tags (Figure 2).
HO
-
n Bu4N
+
O O 6
- P
5
O O 4
3
O
O
HO
O
1
2
OBn
O
HO
O
6
4 5
3
O
2 1
O
NH HN
HN
P
P
Ph Ph Ph Ph
elpanphos-a'
P
P
Ph Ph Ph Ph
naplephos-a"
Figure 1
Figure 2
The ligands were tested in asymmetric allylic substitutions catalyzed by palladium in both traditional solvents and ionic
References
liquids, affording chiral products in ees up to 97%. Further details will be given in the poster.
[1]
Grätzel, M. Nature, 2005, 414, 4764.
[2]
Buscaino, R.; Baiocchi, C.; Barolo, C.; Medana, C.; Gratzel, M.; Nazeeruddin, Md. K.; Viscardi, G. Inorg. Chim. Acta, 2008, 361, 798.
References
[3]
Robb, D. B.; Covey, T. R.; Bruins, A. P. Anal. Chem., 2000, 72, 3653.
[1]
Asymmetric Catalysis on Industrial Scale; Eds: Blaser, H.U.; Schmidt, E. Wiley-VCH: Weinheim, Germany, 2004.
[4]
Dorcier, A.; Dyson, P. J.; McIndoe, J. S. Eur. J. Inorg. Chem., 2003, 4294.
[2]
Benessere, V.; Lega, M.; Ruffo, F.; Silipo, A. Tetrahedron, 2011, 67, 4826 and references therein.
Poster 35
Poster 36
Ferrocene as catalyst in the synthesis of a new polycyclic quinoid compound
Novel palladium-aminocarbene species derived from metal-mediated coupling of
isonitriles and 1,3-diiminoisoindoline
Sara Lentini,a* Alessia Coletti,a Valeria Conte,a Barbara Floris,a Pierluca Galloni.a
Rogério S. Chay,a Konstantin V. Luzyanin,a,b* Armando J. L. Pombeiro,a Vadim Yu. Kukushkinb
a
Dipartimento di Scienze e Tecnologie Chimiche, Università di Rome “Tor Vergata”, via della Ricerca Scientifica, 00133 Roma, Italy,
*[email protected]
a
Centro de Química Estrutural, Instituto Superior Técnico, TU Lisbon, 1049–001 Lisbon, Portugal
b
Department of Chemistry, St. Petersburg State University, 198504 Stary Petergof, Russian Federation
Ferrocene-naphtoquinone dyads show interesting properties in terms of electron-transfer reactions[1]
*[email protected]
and, during our previously project concerning the preparation and investigation of covalently linked dyads,
Metal-mediated coupling of isonitriles in cis-[PdCl2(C≡NR1)2] (R1 = Сy 1, But 2, Xyl 3 CMe2CH2CMe3 4) with one or
a new process for the synthesis of polycyclic quinoid compounds was discovered. Surprisingly, in presence
of ferrocene, the classical condition of the SN2-type reaction between 2-hydroxynaphthoquinone and 1bromoalkanes leads to the formation of a class of polycyclic quinoid derivatives with interesting
photochemical properties
[2,3]
(Figure 1).
two equivs of 1,3-diiminoisoindolinone (9) accomplishes aminocarbenes species [Pd{C(N=C(C6H4CNHN))=N(H)Cy}2]
(10) and [PdCl{C(N=C(C6H4CNHN))=N(H)R1}(CNR1)] (11–13, Scheme 1). Corresponding reaction of cis[PdCl2(CNR1)(PPh3)]
(R1
=
Cy
5,
tBu
6,
CMe2CH2CMe3
8)
with
9
provides
Ferrocene appears to be needful in the reaction and in particular it acts as catalyst. We have made
NH
N
NH
NH
H
H
efforts to understand the mechanism of this new reaction, and we explore the applicability to other
2
N
N
investigated; to this aim different metal complexes, such as cobaltocene and decamethylferrocene, were
Pd
N
considered.
Cy
The uncommon role of cyclopentadienyl metal complexes will be discussed, and in particular their
NH
C
N
N
Cl
Pd
9
NH
1-4
R1
NH
NH
O
Fe
OH
Br
Cl
Scheme 1
Cl
Pd
O
C
K2CO3
9
NH
PPh3
R1
5, 6, 8
HO
Figure 1
[1]
Fukuzumi, S.; Okamoto, K.; Imahori, H. Angew. Chem. Int. Ed. 2002, 41, 620.
[2]
Saikawa, Y.; Hashimoto, K.; Nakata, M.; Yoshihara, M.; Nagai, K.; Ida, M.; Komiya, T. Nature 2004, 429, 363.
[3]
Saikawa, Y.; Moriya, K.; Hashimoto, K.; Nakata, M. Tetrahedron Lett. 2006, 47, 2535.
N
PPh3
H
R1= Cy 14, tBu 15, CMe2CH2CMe2 16
These novel aminocarbenes (10–16) were isolated in good yields (80–90%) and characterized by elemental analyses
(C, H, N), ESI+-MS, IR, 1D (1H,
References
Pd
C
N
O
Cl
N
N
R1
DMSO, 60 °C
O
R1
H
NH
PPh3
O
N
N
R1= tBu 11, Xyl 12, CMe2CH2CMe2 13
R1= Cy 10
nature as catalysis for the one-pot synthesis of the new polycyclic quinoid compounds.
C
C
R1
Cy
Pd
N
N
N
R1
Cl
N
C
C
N
C
H
9
NH
NH
NH
Cl
substrates. Reaction conditions were varied, and in particular, the electrodonating ability of the catalyst was
+
complexes
[PdCl{C(N=C(C6H4CNHN))=N(H)R1}(PPh3)] (14–16).[1]
13
C{1H}) and 2D (1H,1H-COSY, 1H,13C-HMQC/1H,13C-HSQC, 1H,13C-HMBC) NMR
spectroscopies.
Acknowledgments This work has been partially supported by the Fundação para a Ciência e a Tecnologia (FCT), Portugal (FCT projects
PTDC/QUI-QUI/098760/2008 and PTDC/QUI-QUI/109846/2009).
References
[1]
R. S. Chay, K. V. Luzyanin, A. J. L. Pombeiro, M. F. C. Guedes da Silva, V. Yu. Kukushkin, unpublished results.
POSTERS
POSTERS
Poster 37
Poster 38
De-cyclometalation in organoplatinum(II) derivatives: a compared
Pd(II) complexes with tridentate nitrogen-donor ligands: synthesis, characterisation and
experimental-theoretical study
catalytic behaviour in styrene carbonylation.
Luca Maidich,* Antonio Zucca, Sergio Stoccoro, Maria Agostina Cinellu, Marco Masia
Angelo Meduri,a* Daniela Cozzula,b Giacomo Armani,a Ennio Zangrando,a Serafino Gladiali,b
Barbara Milani.a
Department of Chemistry, University of Sassari, Via Vienna, 2, I-07100 Sassari, Italy,
*[email protected]
a
Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste, via L. Giorgieri 1, 34127 Trieste, Italy
b
Dipartimento di Chimica, Università di Sassari, Via Vienna 2, 07100 Sassari, Italy,
2,2’-bipyridine (bipy) is one of the most studied ligands in coordination chemistry. Its behaviour includes classical
*[email protected]
N,N chelation and rollover N,C cyclometalation. In the latter case organometallic complexes arise from the activation of
the C(3’)-H bond, as first observed with iridium[1] and platinum. [2] The clean synthesis of Pt(II) complexes [Pt(bipy-H)(L)(X)]
(L = neutral ligand and X = monoanionic ligand) has been achieved only recently. [3]
During the last decades, CO/styrene copolymers have gained considerable interest, due to the low cost and high
accessibility of the monomers and the possibility of further functionalisation. [1,2] The CO/styrene copolymerisation reaction
The reactivity of complexes [Pt(bipy-H)(L)(CH3)], 1, with acids has been investigated. The outcome of the reaction
is homogeneously catalysed by Pd(II) complexes containing bidentate ligands. [3,4]
strongly depends on several factors, such as the nature of the acid, the properties of the neutral ligand L and the reaction
conditions. A peculiar aspect of these reactions will be reported. Reaction of phosphane derivatives, L=PCy3 (1a), PPh3
(1b),
P(OPh)3 (1c),
with [18-crown-6·H3O][BF4]
readily
leads
to
the
corresponding
cationic
In this work we report the synthesis and characterisation of Pd(II) complexes containing N,N',N''-tridentate ligands
belonging to the family of 2-(2-phenanthrolinyl)-oxazoline derivatives (Figure 1).
complexes
[Pt(bipy*)(L)(CH3)][BF4], 2a-c, where bipy* is a prototropic isomer of 2,2’-bipyridine. In solution these complexes
converts to the corresponding isomers [Pt(bipy)(L)(CH3)][BF4], 3a-c, in which 2-N,C-bipy* has de-cyclometaled.
N
H N
Pt L
Me
Figure 1
H
N
The X-ray analysis of one exponent of this series of complexes evidences
N
Pt L
Me
a dinuclear species where two tridentate ligands chelate one Pd through the
PCy3
a
L = PPh3
b
H
C
speed
P(OPh)3 b
phenanthroline and further connect the other metal with the oxazoline NN
N Pt L
Me
Preliminary kinetic studies indicate that the speed of the isomerization reaction is influenced by at least two factors:
donor (Figure 2).
The
complexes
generate
active
catalysts
for the
CO/styrene
oligomerisation yielding also traces of the corrisponding polyketone. In the
13
C NMR spectrum of the copolymer only the signal of the uu triad is present
(a) the electronic character of the phosphane and (b) the presence of mildly coordinating ligands such as dimethylsulfoxide.
indicating that polyketones with a fully syndiotactic microstructure are
The energies of possible hydride intermediates, [4] as obtained with DFT calculations, follow a trend in fair agreement with
obtained for the first time.
experimental data on reaction kinetics.
References
References
[1]
Drent, E.; Budzelaar, P. H. M., Chem. Rev. 1996, 96, 663.
[1]
Braterman, P. S.; Heat, G. H.; Mackenzie, A. J.; Noble, B.C.; Peacock, R. D.; Yellowlees, K. J. Inorg. Chem., 1984, 23, 3425.
[2]
Durand, J.; Milani, B., Coord. Chem. Rev. 2006, 250, (3-4), 542.
[2]
Skapski, A. C.; Sutcliffe, V. F.; Young, G. B. Chem. Soc., Chem. Commun, 1985, 609.
[3]
Suàrez, E. J. G.; Godard, C.; Ruiz, A.; Claver, C. Eur. J. Inorg. Chem. 2007, 2582.
[3]
Zucca, A.; Petretto, G. L.; Stoccoro, S.; Cinellu, M. A.; Manassero, M.; Manassero, C. ; Minghetti, G.Organometallics, 2009, 28, 2150.
[4]
Nakano, K.; Kosaka, N.; Hiyama, T.;Nozaki, K. Dalton Trans. 2003, 4039.
[4]
Wik, B. J.; Lersch, M.; Tilset, M. J. Am. Chem. Soc., 2002, 124, 12116.
Figure 2
Poster 39
Poster 40
Selective formic acid dehydrogenation catalyzed by Ru complexes
Origin of Intermediate Oxidation States in Planar Tetrapalladium Clusters
Irene Mellone,a,b* Luca Rosi,b Luca Gonsalvi,a Maurizio Peruzzini,a
Kirill Yu. Monakhov,a* Christophe Gourlaouen,b Pierre Braunstein,a
a
b
a
ICCOM-CNR, via Madonna del Piano10, 50019 Sesto Fiorentino (Florence), Italy
Department of Chemistry “Ugo Schiff”, University of Florence, via della Lastruccia 3-13, 50019 Sesto Fiorentino, (Florence), Italy,
Laboratoire de Chimie de Coordination, Institut de Chimie (UMR 7177 CNRS),
Université de Strasbourg, 4 rue Blaise Pascal, F-67081 Strasbourg Cedex, France,
b
*[email protected]
Laboratoire de Chimie Quantique, Institut de Chimie (UMR 7177 CNRS),
Université de Strasbourg, 4 rue Blaise Pascal, F-67081 Strasbourg Cedex, France
*[email protected], [email protected]
Hydrogen is a promising energy carrier and is considered as a clean alternative to fossil fuels. The development of
efficient technologies for hydrogen generation from renewable energy sources and hydrogen storage in a safe and
reversible manner is a prerequisite for the utilization of hydrogen as fuel. [1] Among the different hydrogen storage
materials, formic acid has recently received considerable attention. [2] Formic acid is a liquid at ambient conditions and can
In 1987 Stromnova et al. reported a remarkable cluster, Na2[Pd4{CpMo(CO)3}4] (I), with a unique anionic octanuclear
[Pd4Mo4]2– metal core. It represents the first cluster in which platinum group metals have the unusual average formal
oxidation state (o.s.) of +1/2. The crystal structure of I displays a planar Pd4 core, where each edge-bridging Mo atom is in a
be handled, stored and transported easily.
Formic acid decomposition can occur in two different reactions, known as decarboxylation (or dehydrogenation)
reaction (1) and decarbonylation (or dehydration) reaction (2):
formal zero oxidation state and forms an isosceles triangle with two Pd atoms. Cluster I has been shown to catalyze e.g. the
conversion of alcohols to alkenes.[1] We have performed theoretical calculations to investigate the structure, stability and
bonding of such alkali-metal-palladocycles (Pd4) associated with heteronuclear organometallic moieties (CpTM(CO)3; TM
= Cr, Mo, W) using relativistic DFT in combination with a quantitative energy decomposition analysis (EDA). The
HCOOH
CO2 + H2
HCOOH
CO + H2O (2)
(1)
comparative study with the “Pd4Mn4” cluster [(CO)Pd(NC)Mn(C5H4Me)(CO)2]4[2] containing an orthogonal arrangement of
helical units has been carried out. On the basis of molecular modeling, electronic structure calculations, EDA and electron
localization function (ELF) analyses, we could gain an insight into their structures and explain the stability and reactivity of
double open-faced [Pd4{CpTM(CO)3}4]2– structures associated with alkali-metal countercations (M+ = Li+, Na+, K+) (Figure
We investigated the selective decomposition of HCO 2H/NEt3 (5:2) azeotropic mixture to H2 and CO2 in the presence
of different homogeneous ruthenium catalysts stabilized by the tripodal ligands triphos and NP3, both as preformed
1). Finally, we address an almost 25-years-old question “what is the origin of intermediate oxidation states in such kind of
molecular systems?”.
complexes and as in situ reaction mixtures. The results showed that in all systems full conversion of formic acid was
achieved and no CO was detected by FT-IR spectroscopy in the gas mixture. Moreover, it was observed that the activity of
Ru-triphos catalysts is higher than that of Ru-NP3 catalysts and preliminary mechanistic interpretation of data will be
presented.
Acknowledgements The authors thank CNR-DPM for support through projects PIRODE and EFOR.
References
[1]
(a) Armaroli, N.; Balzani, V. Angew. Chem. Int. Ed., 2007, 46, 52. (b) Züttel, A.; Borgschulte, A.; Schlapbach, L. in Hydrogen as a
Future Energy Carrier, JG de Vries, CJ Elsevier, Wiley-VCH, Weinheim, 2008.
[2]
(a) Fellay, C.; Yan, N.; Dyson, P. J.; Laurenczy, G. Chem. Eur. J., 2009, 15, 3752. (b) Loges, B.; Boddien, A.; Gärtner, F.; Junge, H.;
Figure 1
Beller, M. Top Catal., 2010, 53, 902.
References
[1]
(a) Stromnova T. A.; Busygina I. N.; Katser S. B.; Antsyshkina A. S.; Porai-Koshits M. A.; Moiseev, I. I. J. Chem. Soc, Chem. Commun.
1988, 114. (b) Moiseev, I. I. Russ. Chem. Rev. 1989, 58, 682. (c) Moiseev I. I.; Stromnova T. A.; Vargaftik, M. N. J. Mol. Cat. 1994, 86,
71. (d) Stromnova T. A.; Shishilov O. N.; Dayneko M. V.; Monakhov K. Yu.; Churakov A. V.; Kuz’mina L. G.; Howard, J. A. K. J.
Organomet. Chem. 2006, 691, 3730.
[2]
Braunstein P.; Oswald B.; Tiripicchio A.; Tiripicchio Camellini, M. Angew. Chem. Int. Ed. 1990, 29, 1140.
POSTERS
POSTERS
a
Poster 41
Poster 42
One-electron oxidative addition of radicals on Copper (I) complexes
Reactivity of arene ruthenium (II) complexes with N- and O- chelating ligands.
Aurélie Morin,a* Yohan Champouret,a Rinaldo Poli.a,b
Andrew D.Phillips, Maryam Mohammadpoor, Crystal O’Connor*
CNRS, Laboratoire de Chimie de Coordination (LCC), 205, route de Narbonne, 31077 Toulouse, France and Ecole Nationale Supérieure des
School of Chemistry and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland.
Ingénieurs en Arts Chimiques et Technologiques (ENSIACET), 4, allée Emile Monso, 31030 Toulouse, France;
e-mail: [email protected], *[email protected]
b
Institut Universitaire de France, 103, boulevard Saint Michel, 75005 Paris, France
*[email protected]
The last decade has witnessed a real explosion of research in the area of controlled radical polymerization (CRP) [1,2]
which relies on the reversible exchange of propagating radical chains with various dormant species. This can happen via
degenerative transfer, atom transfer (ATRP), or a variety of other reversible deactivation strategies. Each different
controlling method suffers from limitation with the range of polymerizable monomers. The copolymerization of olefins
with polar monomers, such as vinyl acetate and ethylene, remains a great challenge.
Organometallic-mediated radical polymerization (OMRP)[3] is described in scheme 1. The growing radical chain (P˙)
is reversibly trapped by the Mt zLn complex through a one-electron oxidative addition process to form a P-Mtz+1Ln complex
as a dormant species.
A series of 6-benzene ruthenium(II) complexes bearing an anionic -saturated 5-memeber hetero-ligand have been
synthesized and characterized using standard techniques, including solution NMR, X-ray diffraction and UV-visible
spectroscopy. The chelating ligand consists of O,O’ – acetylacetone (acac, 1) and N,O – ketiminate (nacac, 2). Importantly,
the reactivity of these complexes can be compared to the corresponding β-diketiminate (nacnac, 3) complexes reported by
Phillips et al.
Previously we reported that the majority of 6-arene β-diketiminato-ruthenium (II) chloride complexes are air
sensitive,1 while we intend to show that corresponding acac and nacac complexes are air stable, but differ considerably in
overall reactivity. Formation of the cationic complexes bearing an acac or nacac supporting ligand required more forceful
conditions,[1] i.e., AgOTf to abstract the chloride co-ligand. Moreover, the triflate moiety is found coordinated to the Ru
centre.
R
Ru
O Cl O
R
Ru
O Cl N
Ru
N Cl N
R
(1)
R
R
R
(2)
(3)
Scheme 2: OMRP mechanism
R = H, Me, iPr
With an OMRP mechanism the control of the polymerization is determined, in addition to kinetic factors, by the
Scheme 1: RuCl complexes of acac (1), nacac (2) and nacnac (3)
trapping equilibrium constant (KOMRP) which only depends on the homolytic metal-carbon bond strength. One advantage of
the OMRP process is that the metal-carbon bond strength can be easily tuned by the steric and electronic properties of the
ligand around the coordination sphere.
We present here the synthesis of copper(I) complexes and their uses in radical polymerization of “difficult”
monomers: ethylene and vinyl acetate. Trispyrazolylborate and β–diketiminate ligand have been chosen as they can be
Furthermore, 6-benzene Ru(II) acetylacetone (acac) complexes bearing triflate do not form a dimeric species as
previously reported in the case when p-cymene is employed as the coordinating 6-arene.[2] Finally we present calculated
high-level DFT models to further elucidate the internal electronic structure of three types of complexes, and correlate
experimental spectroscopic data, i.e. UV-visible spectra.
tuned to make the copper-carbon bond dissociation energy suitable for the control of ethylene and vinyl acetate
polymerization.
References
[1]
Matyjaszewski, K.; Davis, T. P. Hanbook of Radical Polymerization Ed.; John Wiley and Sons, Inc.: Hoboken, 2002.
[2]
Matyjaszewski, K.; Ganou, Y.; Leibler, L.; Macromolecular Engineering: Precise Synthesis, Materials Properties, Applications Ed;
Wiley-VCH Verlag GmbH: 2007.
[3]
Poli, R. Angew. Chem. Int. Ed., 2006, 45, 5058.
References
[1]
Phillips, A. D.; Laurenczy, G.; Scopelliti, R.; Dyson, P. J. Organometallics, 2007, 26, 1120.
[2]
Sumiyoshi T.; Gunnoe T. B.; Peterson J. L.; Boyle P. D. Inorg. Chim. Acta, 2008, 361, 3254.
Poster 43
Poster 44
Olefin Methatesis Ru-Catalysts with a Syn Substituted N-heterocyclic Carbene Backbone
Metal-Assisted Formation of New Hydroxy(pyrazolyl)diphenylborate Ligands
Alessandra Perfetto,* Chiara Costabile, Pasquale Longo, Fabia Grisi
Riccardo Pettinari,a* Fabio Marchetti,b Claudio Pettinari,a Corrado Di Nicola,a
Ivan Timokhin,b Aurel Tabacaru,b Magda Monaric
Dipartimento di Chimica e Biologia, Università di Salerno, Via Ponte don Melillo I-84084 Fisciano (Sa), Italy.
*[email protected]
a
b
Olefin metathesis has emerged as a powerful synthetic tool for the formation of new C-C bond; its success in different
c
chemistry fields has been driven by the development of increasingly efficient catalysts. [1] Ruthenium-based catalysts have
School of Pharmacy, Via S. Agostino 1, 62032 Camerino (MC), Italy,
School of Science and Technology, Via S. Agostino 1, 62032 Camerino (MC), Italy
Dipartimento di Chimica “G. Ciamician”, UniVersita` di Bologna, Via Selmi 2, I-40126 Bologna, Italy
*[email protected]
received considerable attention because of their tolerance to moisture, oxygen, and a large number of organic functional
Due to their potential applications in many areas, half-sandwich η5-pentamethylcyclopentadienyl
groups. Moreover, catalyst activity can be adapted by fine-tuning the structure and the electronic properties of the ligands
around the ruthenium center.[2]
Rh/Ir(III) complexes have been widely investigated. [1] Also Rh(III) and Ir(III) complexes containing
Recently, we focused on the preparation of ruthenium complexes bearing syn and anti-methyl substituents on the Nheterocyclic carbene (NHC) backbone and o-tolyl or o-isopropyl groups at the nitrogen atoms of the NHC ring.3 These
scorpionates ligands[2] have recently attracted considerable attention because of their ability to activate the
aliphatic and aromatic C-H bonds of hydrocarbons and other substrates.[3]
catalysts showed high efficiency in ring closing metathesis (RCM) reactions and the syn isomers, in particular, revealed
among the most active catalysts known in the RCM of hindered olefins up to now.
To further investigate the pivotal role of the symmetry of the NHC backbone in the Ru-catalyst activity, here we report
As an extension of ours previous works,[4] here we report a systematic study of the reactions of the
[MCp*Cl2]2 dimers (M = Rh, Ir) with the bis(pyrazolyl)diphenylborate KPh2Bpz2 ligand. Beside the
the synthesis of new catalysts with differently encumbered syn substituents on the NHC backbone and N-aryl groups.
previously observed B-N hydrolysis, here we report on the metal-assisted formation of a new
Preliminary catalytic results of standard RCM tests are also presented.
hydroxyl(pyrazolyl)diphenylborate ligand (scheme 1).
R'
R''
N
R''
N
Cl
R R
Ru
Cl
R'
R''
R''
N
R
R'
R'
N
Cl
Ru
R
Cl
Ph
PCy3
O
R''= Ph; Me, aryl
R'= Ph; Me.
Figure 1
References
[1]
Selected reviews: (a) Vougioukalakis, G. C.; Grubbs, R. H. Chem. Rev. 2010, 110, 1746. (b) Samojłowicz, C.; Bieniek, M.; Grela, K.
Scheme 1
Chem. Rev. 2009,109, 3708. (c) Grubbs, R. H. Handbook of Metathesis; Wiley-VCH: Weinheim, Germany, 2003.
[2]
(a) Grubbs, R. H. J. Macromol. Sci., Part A: Pure Appl. Chem. 1994, A31, 1829. (b) Tmka, T. M.; Grubbs, R. H. Acc. Chem. Res. 2001,
34, 18.
[3]
(a) Grisi, F.; Costabile, C.; Gallo, E.; Mariconda, A.; Tedesco, C.; Longo, P. Organometallics 2008, 27, 4649. (b) Grisi, F.; Mariconda,
References
[1]
Liu, J.; Wu, X.; A. Iggo, J.; Xiao, J. Coord. Chem. Rev. 2008, 252, 782.
[2]
(a) Trofimenko, S. Scorpionates - The Coordination Chemistry of Polypyrazolylborate Ligands; Imperial College Press: London, 1999.
(b) Pettinari, C. Scorpionates II: Chelating borate ligands; Imperial College Press: London, 2008.
A.; Costabile, C.; Bertolasi, V.; Longo, P. Organometallics 2009, 28, 4988. (c) Costabile, C.; Mariconda, A.; Cavallo, L.; Longo, P.;
Bertolasi, V.; Ragone, F.; Grisi, F. Chem. Eur. J., in press.
[3]
Slugovic, C.; Padilla-Martínez, I.; Sirol, S.; Carmona, E. Coord. Chem. Rev. 2001, 213, 129.
[4]
(a) Pettinari, C.; Pettinari, R.; Marchetti, F.; Fianchini, M.; Skelton, B. W.; White, A. H. Inorg. Chem. 2005, 44, 7933; (b) Pettinari, C.;
Pettinari, R.; Marchetti, F.; Macchioni, A.; Zuccaccia, D.; Skelton, B. W.; White, A. H. Inorg. Chem. 2007, 46, 896.
POSTERS
POSTERS
Poster 45
Poster 46
Synthesis of Shiff-bases ruthenium(II) arene complexes
Catalytic dehydrogenation of alcohols by iridium pincer complexes
Riccardo Pettinari,a* Fabio Marchetti,b Claudio Pettinari,a Corrado Di Nicola,b
Alexey V. Polukeev,a* Pavel V. Petrovskii,a Alexander S. Peregudova, Mariam G. Ezernitskaya,a
Serena Orbisaglia,b Adriano Pizzabiocca,a Augusto Cingolani,b
Avthandil A. Koridze a,b
a
b
a
School of Pharmacy, Via S. Agostino 1, 62032 Camerino (MC), Italy
A.N.Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 Vavilov Street, 119991 Moscow, Russia
b
School of Science and Technology, Via S. Agostino 1, 62032 Camerino (MC), Italy
Institute of Organometallic Chemistry, I. Javakhishvili Tbilisi State University, 3 Chavchavadze Avenue, 0128 Tbilisi, Georgia
*[email protected]
*[email protected]
The supply of secure, clean and sustainable energy is arguably the most important scientific and technical challenge
Half-sandwich ruthenium compounds with the general formula [(η6-arene)Ru(XY)(Z)] (where XY is a bidentate
chelating ligand; and Z a monodentate ligand) have recently gained much attention as promising antitumor agents. [1] Recent
facing humanity in the 21st century.[1] Hydrogen is potentially an ideal energy carrier, as it is nonpolluting and has a high
studies have shown that the aqueous behavior of these ruthenium(II) compounds is highly dependent on the identity of the
energy density by weight. To accrue the full environmental benefit of hydrogen as an energy carrier, low-carbon intensive,
ligands and especially of the chelating one.[1] In extension of our previous work on ruthenium derivatives containing
low polluting, and lower cost processes for producing hydrogen from renewable energy sources need to be developed.[2] In
acylpyrazolones ligands,[2] we have undertaken a systematic study of the reactions between the [Ru(arene)Cl2] dimers (arene
= p-cymene or benzene) and some Shiff bases (HL’) obtained from condensation reactions involving acylpyrazolones (HQ’)
this respect, alcohols hold some promise as liquid organic hydrogen carriers. [3] In the present work we report the results of
our investigation the activity of bis(phoshinite) complex 1 and the related complexes, 2 and 3, as catalysts for the
dehydrogenation of alcohols (Figure 1).
(Scheme 1).
NH2
R3
Me
N
R3
O
N
Me
N
OH
R1
HQ'
N
N
R1 = Me or Ph
R3 = Me, Ph or naphthyl
OH
R1
HL'
Figure 1
Scheme 1
Turnover numbers up to 2500 can be achieved for the dehydrogenation of secondary alcohols such as 1-phenylethanol
in neat substrate as the reaction media; this result is further improved upon dilution of the catalytic system with hydrocarbon
Me
Me
Me
Ru
R3
Me
Cl
O
1
N N R
solvent. In contrast to secondary substrates, primary alcohols readily undergo decarbonylation even at ambient temperature.
The reaction of complex 1 with ethanol was studied in detail (Figure 2). The mechanism of this transformation, as well as
the observed trends in catalytic activity will be discussed.
N
Figure 1
Figure 2
The new [(arene)Ru(L’)Cl] complexes, containing the N,O-chelating Shiff bases (Figure 1) have been synthesized and
fully characterized. Their biological activity is currently under investigation.
Acknowledgements This work was supported by The Nominal Competitive Grant of a Name of Academician K.I. Zamaraev (2011).
References
References
[1]
N. Farrell, Bioorganometallics, ed.G. Jaouen, Wiley-VCH, Weinheim, 2005.
[1]
Lewis, N. S.; Nocera, D. G., PNAS, 2006, 103, 15729.
[2]
F. Marchetti; C. Pettinari; R. Pettinari; A. Cerquetella; A. Cingolani; E. J. Chan; K. Kozawa; B. W. Skelton; A. H. White; R. Wanke, M.
[2]
Lubitz, W.; Tumas, W., Chem. Rev., 2007, 107, 3900.
L. Kuznetsov; L. M. D. R. S. Martins; A. J. L. Pombeiro, Inorg. Chem. 2007, 46, 8245.
[3]
Johnson, T. C; Morris, D. J.; Wills, M., Chem. Soc. Rev., 2010, 39, 81.
Poster 47
Poster 48
Synthesis, Characterization and Preliminary Luminescence Studies of new Cyclic
Low-Temperature Kinetic NMR Studies on the Single Insertion of Olefin into the Zr-C
Trinuclear Heterobimetallic Cu(I)/Au(I) Complexes.
Bond: Assessing the Counterion-Solvent Interplay
Simone Ricci,a* Alfredo Burini,a Rossana Galassi,a Roy McDougald Jr,b Vladimir Nesterov,b
Luca Rocchigiani,* Gianluca Ciancaleoni, Cristiano Zuccaccia, Alceo Macchioni
b
Mohammad A. Omary
Dipartimento di Chimica dell’Università degli Studi di Perugia, Via Elce di Sotto 8, I-06123 Perugia, Italy
a
*[email protected]
School of Science and Technology, Chemistry Division, Via S. Agostino 1, 62032 Camerino (MC), Italy,
b
Department of Chemistry, University of North Texas, Denton, Texas, 76203 (USA)
The insertion of olefin into the metal-carbon bond is the elemental step of the Ziegler-Natta catalysis that, in the
*[email protected]
homogeneous phase, occurs through the initial association of the olefin with the metal cation of the catalytic ion pair.
The chemistry of gold-heterometal complexes bearing unsupported closed-shell metallophilic interactions has grown
Group IV metallocenium ion pairs polymerize olefins with high rates, but the elevate reactivity of such systems
rapidly in the last years as a result of the increasing interest in the intrinsic nature of these interactions [1] commonly
dramatically complicates fundamental kinetic investigations. During our studies on the self-aggregation of zirconocenium
associated to photoluminescent properties.[2] Here we report the synthesis and the preliminary luminescence studies of a
ion pairs,[1,2] we synthesized some zirconazidirines having ([Cp2Zr(2-CH2-NR1R2)][X] as general formula that show some
novel class of trinuclear gold-copper metallocycles. The heterobimetallic cycles with different metal framework Au2Cu and
remarkable requisites to be used as good models for investigating the single insertion of olefin into the Zr-C bond. In
Cu2Au have been obtained by reacting the trinuclear gold(I) imidazolates, namely {Au[μ-1-bzIm]}3 or {Au[μ-1-meIm]}3
particular, they are able to react stoichiometrically with olefins leading to a five-membered azametallacycle, as represented
(where 1-bzIm = 1-benzylimidazolate and 1-meIm = 1-methylimidazolate) with the trinuclear copper(I) pyrazolate {Cu[μ-
in Figure 1.
3,5-(CF3)2pz]}3 (where 3,5-(CF3)2Pz = bis-3,5-trifluoromethyl-pyrazolate) in different stoichiometric ratios. The trinuclear
heterobimetallic cyclic complexes [Au2(1-MeIm)2Cu(μ-3,5-(CF3)2pz] (1) and [Au2(1-bzIm)2Cu(μ-3,5-(CF3)2pz] (2) were
characterized by X-ray diffraction. They exhibit good stability in the solid state with an intense green emission when
irradiated at 366 nm at room temperature. The figure below reported shows a portion of the crystal packing of the complex
1 and its emission spectrum highlighting the emissive behavior at different temperatures with 350 nm as excitation
wavelength.
77 K
90 K
100 K
110 K
120 K
130 K
140 K
150 K
175 K
200 K
250 K
298 K
7
Intensity in Arb. Units
1,0x10
6
8,0x10
ex = 350 nm
6
6,0x10
6
4,0x10
Figure 1
With the aim of obtaining thermodynamic activation parameters of the single insertion and determining as they depend
on nature of counterion and solvent, low-temperature kinetic NMR studies of the reaction of 2-methyl-1-heptene with
[Cp2Zr(2-CH2-NMePh)][X] [1a:X- = MeB(C6F5)3-; 1b:B(C6F5)4-] ion pairs were performed. Results indicate that, in
toluene, H‡ is higher for MeB(C6F5)3- than for B(C6F5)4- (H‡=-4.5 kcal mol-1) but the former better compensates the loss
6
2,0x10
of entropy caused by olefin association (S‡=-13 cal mol-1 K-1). The two ion pairs 1a-b behave exactly the same in a
0,0
400
450
500
550
600
650
700
Wavelength in nm
toluene/chlorobenzene mixture due to the coordination of a chlorobenzene molecule at the zirconium center that pushes the
References
counterion in the second coordination sphere. H‡ (ca 11 kcal mol-1) is higher than in toluene (H‡=8.5 kcal mol-1 and
[1]
(a) Pykkö, P. Angew. Chem. Int. Ed. 2004, 43, 4412. (b) Pykkö, P. Chem. Soc Rev. 2008, 37, 1967.
H‡=4.0 kcal mol-1 for 1a and 1b, respectively) while S‡ (ca -26 cal mol-1 K-1) is similar to that of 1a in toluene (S‡=-32
[2]
(a) Fernandez, E. J.; Laguna, A.; López-de-Lazuriaga, J. M. Dalton Trans. 2007, 1969. (b) López-de-Lazuriaga, J. M. in Modern
cal mol-1 K-1).
Supramolecular Gold Chemistry (Ed.: Laguna, A.), Wiley-VCH. Weinheim, 2008, p 347.
References
[1]
Rocchigiani, L.; Zuccaccia, C.; Zuccaccia, D.; Macchioni, A. Chem .Eur. J. 2008, 14, 6589.
[2]
Rocchigiani, L.; Bellachioma, G.; Ciancaleoni, G.; Macchioni, A.; Zuccaccia, D.; Zuccaccia, C. Organometallics 2011, 30, 100.
POSTERS
POSTERS
Poster 49
Poster 50
Bulky Tris(phenylpyrazolyl)methanesulfonate Copper Complexes
A Spectroscopic and Mechanistic Investigation on the Dynamic Resolution of Lithiated
with unsaturated molecules
Trifluoromethylstyrene Oxides
Bruno G. M. Rocha,* Konstantin Luzyanin, Riccardo Wanke, M. Fátima C. Guedes da Silva,
Antonio Salomone,* Rosmara Mansueto, Filippo Maria Perna, Saverio Florio and Vito Capriati
Luísa M. D. R. S. Martins, Armando J. L. Pombeiro
Università di Bari “Aldo Moro”, Dipartimento Farmaco-Chimico, Consorzio Interuniversitario Nazionale Metodologie e
Processi Innovativi di Sintesi C. I. N. M. P. I. S., Via E. Orabona 4, I-70125 – Bari, Italy,
Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
*[email protected]
*[email protected]
Stereoselective substitution of organolithiums represents a powerful methodology in asymmetric synthesis. While it is
In this work the synthesis of the sterically hindered and water soluble tris(3-phenylpyrazolyl)methane sulfonate
Ph -
(Tpms ) (1) has been optimized
[1]
I
and its reactivity towards Cu was studied. Thus, the isocyanide or carbonyl Cu(I)
complexes [Cu(TpmsPh)(L)] [L = CyNC (cyclohexyl isocyanide) (4), XyNC (2,6-dimethylphenyl isocyanide) (6) or CO (3)],
Ph -
bearing the sterically hindered scorpionate tris(3-phenylpyrazolyl)methanesulfonate (Tpms ) , were prepared from reaction
much convenient to use configurationally stable reagents, it is also possible to carry out an asymmetric synthesis by using
stereolabile organolithiums that undergo fast racemization. This goal, usually achieved by exploiting a dynamic resolution
of the racemic organolithium, provides an opportunity to obtain enantioenriched products starting from racemic substrates
of [Cu(Tpms )(MeCN)] (2) with the appropriate isocyanide or CO. XyNC in 6 is displaced by 3-iminoisoindolin-1-one to
with the aid of external chiral ligands. As part of our research on the reactivity of -lithiated aryloxiranes,[1] we recently
afford the corresponding complex 7 (the first Cu compound with this ligand), whereas the ligated acetonitrile in 2 undergoes
found that although -lithiated trifluoromethyl-substituted aryloxiranes undergo fast racemization when generated in THF,
Ph
Ph
nucleophilic attack by methylamine to give the amidine complex [Cu(Tpms ){MeC(=NH)NHMe}] (5). In all the
the employment of hexane/TMEDA dramatically hinders their racemization. [2]
complexes the scorpionate facially caps the metal in the N,N,O-coordination mode involving the sulfonate moiety in the
coordination to the copper centre.
In this communication, we report preliminary results concerning the dynamic resolution of -lithiated
trifluoromethylstyrene oxides, in the presence of chiral diamine ligands. Solution structure and racemization mechanism
will also be discussed in light of DFT calculations and a multinuclear magnetic resonance investigation.
References
[1]
Capriati, V.; Florio, S.; Salomone, A. “Oxiranyllithiums as Chiral Synthons for Asymmetric Synthesis” Chapt. 4 in Stereochemical
Aspects of Organolithium Compounds, Ed. Gawley, R. E., Vol. 26 in “Topics in Stereochemistry”, Ed. Siegel, J. S.,Verlag Helvetica Acta,
Zürich, 2010, pp 135164.
Acknowledgements This work has been partially supported by the Fundação para a Ciência e a Tecnologia (FCT), Portugal (including FCT
project PTDC/QUI-QUI/098760/2008).
References
[1]
Wanke, R.; Smolenski, P.; Guedes da Silva, M. F. C.; Martins, L. M. D. R. S.; Pombeiro, A. J. L. Inorg. Chem., 2008,47, 10158.
[2]
(a) Capriati, V.; Florio, S.; Perna, F. M.; Salomone, A. Chem. Eur. J. 2010, 16, 9778. (b) Perna, F. M.; Salomone, A.; Dammacco, M.;
Florio, S.; Capriati ,V. Chem. Eur. J. 2011, DOI: 10.1002/chem.201100351.
Poster 51
Poster 52
Bis(pyrazolyl)methane derivatives complexes incorporating stables free radicals
Penthamethyl-cyclopentadienyl-iridium molecular catalysts for water oxidation
of the 1,3-bisdiphenylene-2-phenylallyl (BDPA) kind
Arianna Savini,* Paola Belanzoni, Gianfranco Bellachioma, Cristiano Zuccaccia,
Carina Santos,* Gonzalo Rincón-Llorente, Margarita Gómez, Eleuterio Álvarez
Daniele Zuccaccia, and Alceo Macchioni
Inst. de Investigaciones Químicas, CSIC y Universidad de Sevilla, Avda. de Americo Vespucio 49, Isla de la Cartuja. 41092 Sevilla, España,
Department of Chemistry, University of Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy,
*[email protected]
*[email protected]
Water oxidation is an essential process for constructing an artificial photosynthetic apparatus [1-2] aimed at the splitting
Bis(pyrazolyl)alkanes (R2C)n(pzx)2, are a family of stable and flexible bidentate ligands. They are isoelectronic and
By simple
of H2O into H2 and O2, whose realization would contribute to solve the worldwide energetic problem in a green and
synthetic procedures, their coordination behaviour can easily be tuned by exchanging the steric and electronic characteristic
sustainable way.[3] In addition being endoergonic, water oxidation is also difficult from the kinetic point of view.
isosteric with bis(pyrazolyl)borates which are another well known family also discovered by Trofimenko.
of the substituents in the pyrazolyl rings.
[2]
[1]
This reason makes poly(pyrazolyl)alkanes, particularly bis(pyrazolyl)methane,
very popular polydentate donor nitrogen ligands and they form a large variety of coordination compounds containing
Consequently, an efficient catalytic system is necessary, capable of interfacing the monoelectronic charge separation
process with the multielectron oxidative one.
transition and representative elements.[3] Bis(pyrazolyl)alkanes present a richer chemistry in comparison with their boron
Following the pioneer studies of Meyer and co-workers on the “blue dimer”,[4] a series of dinuclear and mononuclear
counterparts. Thus, bis(pyrazolyl)methane form stable adducts containing six member rings, basic salts, products coming
molecular catalysts for water oxidation have been described. [5] Among them iridium(III) catalysts[6-9] proved to be
from the C(sp3)-N bond cleavage and agostic interaction M··H-C between the metallic centre and the methylene bridge
particularly robust showing TONs up to a few thousands.
protons. Free radicals are compounds which are often uncharged molecules having an unpaired valence electron
In this contribution, a critical analysis of the factors affecting the activity of molecular iridium catalysts for water
consequently on an open shell electronic configuration. Despite the high reactivity of free radicals which do not allow them
oxidation based on the Cp*-Ir moiety (Cp* = penthamethyl-cyclopentadienyl ligand) and their possible degradation
to be neither isolated nor characterised there is a group of them, known as stable free radicals that are relatively inert.
pathways will be presented. Degradation studies were carried out under catalytic conditions [strong acidic and oxidizing
Koelsch’s free radicals 1,3-bisdiphenylene-2-phenylallyl (BDPA)[4] is a good example of this kind of radicals.
environment by HNO3 and Ce(IV), respectively] by a combined experimental (in situ NMR, UV-VIS and oximetry) and
In this study we wanted to observe the influence of the addition of different derivatives of the stable BDPA free
theoretical (DFT) approach.
radicals in the pyrazolyl ring and how this affects the properties and coordination of the metallic complexes.
References
[1]
Grätzel, M. Acc. Chem. Res. 1981, 14, 376.
[2]
Meyer, T. J. Acc. Chem. Res. 1989, 22, 163.
[3]
Balzani, V.; Credi, A.; Venturi, M. ChemSusChem 2008, 1, 26.
[4]
Gersten, S. W.; Samuels, G. J.; Meyer, T. J. J. Am. Chem. Soc. 1982, 104, 4029.
[5]
Sala, X.; Romero, I.; Rodríguez, M.; Escriche, L.; Llobet, A. Angew. Chem. Int. Ed. 2009, 48, 2842.
[6]
McDaniel, N. D.; Coughlin, F. J.; Tinker, L. L.; Bernhard, S. J. Am. Chem. Soc. 2008, 130, 210.
[7]
Hull, J. F.; Balcells, D.; Blakemore, J. D.; Incarvito, C. D.; Eisenstein, O.; Brudvig, G. W.; Crabtree, R. H. J. Am. Chem. Soc. 2009, 131,
8730. Blakemore, J. D.; Schley, N. D.; Balcells, D.; Hull, J. F.; Olack, G. W.; Incarvito, C. D.; Eisenstein, O.; Brudvig, G. W.; Crabtree,
R. H. J. Am. Chem. Soc. 2010, 132, 16017.
[8]
Lalrempuia, R.; McDaniel, N. D.; Müller-Bunz, H.; Bernhard, S.; Albrecht, M. Angew. Chem. Int. Ed. 2010, 49, 9765. Dzik, W. I.; Calvo,
S. E.; Reek, J. N. H.; Lutz, M.; Ciriano, M. A.; Tejel, C.; Hetterscheid, D. G. H.; de Bruin, B. Organometallics 2011, 30, 372.
Hetterscheid, D. G. H.; Reek, J. N. H. Chem. Commun. 2011, 47, 2712.
References
[9] Savini, A.; Bellachioma, G.; Ciancaleoni, G.; Zuccaccia, C.; Zuccaccia, D.; Macchioni, A. Chem Commun. 2010, 46, 9218.
[1]
Trofimenko, S., J. Am. Chem. Soc. 1970, 92, 5118.
[2]
(a) Trofimenko, S., Chem. Rev. 1993, 93, 943-980. (b) Trofimenko, S. Scorpionates: The coordination chemistry of polypyrazolyborate
ligands; Imperial College Press: London, UK,1999. (c) Pettinari, C. Scorpionates II: Chelating Borate Ligands;Imperial College
Press:London, UK, 2008.
[3]
Pettinari, C.; Pettinari R. Coordination Chemistry Reviews, 2005, 249, 663.
[4]
Koelsch, C.F., J. Am. Chem. Soc. 1957, 79, 4439.
POSTERS
POSTERS
Poster 53
Poster 54
Mono- and dinuclear gold(I/III) complexes of 2-pyridyl(2-benzimidazole): synthesis,
Anionic and Carbene Palladium(II) Complexes as Catalysts of Suzuki-Miyaura Reaction
3
structure and catalysis in A -reaction of aldehydes, amines, and alkynes in water
Ewelina Silarska,* Anna M. Trzeciak
M. Serratrice,* M. A. Cinellu, L. Maiore, F. Cocco, A. Zucca, S. Stoccoro
Faculty of Chemistry, University of Wroclaw, 14 F.Joliot-Curie, 50-387 Wrocław, Poland
*[email protected]
Department of Chemistry, University of Sassari, Via Vienna 2, I-07100 Sassari, Italy
*[email protected]
The catalytic activity of Pd(II) square planar complexes of the type [IL] 2[PdCl4][1,2] and π-allyl palladium complexes
In the last decade, homogeneous catalysis by gold species, both Au(I) and Au(III), has attracted much attention due to
the great variety of versatile transformations that can be carried out.
[(IL)Pd(allyl)Cl][3] with imidazolium or pirydynium groups (IL) have been tested in Suzuki-Miyaura reaction of 2bromotoluene with phenyl boronic acid carried out in isopropanol and water at 40°C with a microwaves as a heating
[1]
A variety of gold(I) complexes have been successfully exploited as catalysts, while the most employed gold(III)
catalyst is AuCl3, a very hygroscopic, acidic, light sensitive, and relatively powerful oxidant species. Very recently, a
number of coordination and organometallic compounds have been developed which offer valuable alternatives to AuCl 3.
source. The results depend on the structure of catalyst precursor. The highest yield (90%) was obtained for [dmiop] 2[PdCl4]
(dmiop-1,2-dimethyl-3-propoxymethylene imidazolium cation) and complexes with bulky cations – [H.SIMes] (1,3Bis(2,4,6-trimethylphenyl) imidazolinium cations), [H.IPr] (1,3-Bis(2,6-diisopropylphenyl) imidazolinium cations) (80%)
These complexes, besides being more air- and moisture-stable, and molecularly well-defined, can be heterogenized after
in a 1:1 mixture of isopropanol and water. During the reaction Pd 0 nanoparticles have been formed from the palladium(II)
functionalization of the ligands. Most of the ligands that have been used so far are polydentate ligands containing at least
precursors. Use a microwaves reduced a time of reaction and increased the yields of 2-methylbiphenyl. The activity of
anionic and carbene complexes of palladium have been compared. In the presence of water a catalytic activity of carbene
one iminic N-donor, usually of a pyridine ring or of a Schiff base.
Since many years our research group has been involved in the synthesis of gold complexes - mainly gold(III)
complexes were lower than anionic complexes. In a alcohol medium results were similar.
derivatives - with nitrogen donor ligands, such as variously substituted 2,2’-bypiridines, pyridinyl-oxazolines and
phenanthrolines. A number of innovative species have been obtained, e.g. the first gold(III) oxo-bridged dinuclear
complexes, some of which have been found to promote the catalytic polymerization of styrenes. [2]
Following our interest in this field, here report the synthesis of mono- and dinuclear gold(I,III) derivatives of 2pyridyl(2-benzimidazole) (pbiH) and preliminary results of their catalytic activity in the synthesis of propargylamines via a
three-component coupling reaction (A3-reaction) of aldehydes, amines and alkynes in water.
O
R
Au complex
H
+
N
H
R=R'= Ph
+
R'
H
N
-H2O
R
R'
References
[1]
AA.VV. Chem. Rev. 2008, 108.
[2]
Cinellu, M. A.; Maiore, L.; Minghetti, G.; Cocco, F.; Stoccoro, S.; Zucca, A.; Manassero, M.; Manassero, C. Organometallics 2009, 28,
7015.
References
[1]
Zawartka, W.; Trzeciak, A. M.; Ziółkowski, J. J.; Lis, T.; Ciunik, Z.; Pernak, J. Adv. Synth. Catal., 2006, 348, 1689.
[2]
Zawartka, W.; Gniewek, A.; Trzeciak, A. M.; Ziółkowski, J. J.; Pernak , J. J. Mol. Catal. A: Chem., 2009, 304, 8.
[3]
Marion, N.; Nolan, S.P. Acc. Chem. Res., 2008, 41, 1440.
Poster 55
Poster 56
Neutral N-Donor Ligands derived from Norharman
Synthesis of new N-heterocyclic carbene ligands and related coinage metal complexes
R. J. Thatcher,a Gavino Solinas,b* R. E. Douthwaitea
Andrea Trasatti,* Giancarlo Gioia Lobbia, Marika Marinelli, Barbara Morresi, Grazia Papini, Maura Pellei,
Carlo Santini
a
b
Department of Chemistry, University of York Heslington, York, YO10 5DD, (UK)
Dipartimento di Chimica Fisica ed Inorganica, viale Risorgimento 4, I-40136 Bologna, (I)
School of Science and Technology, Chemistry Division, Via S. Agostino 1, 62032 Camerino (MC), Italy
*[email protected]
*[email protected]
Metal complexes of nitrogen-donor ligands exhibit some of the most interesting stoichiometric and useful catalytic
Over the last decade, several reviews have appeared describing the most recent developments with regard to design,
transformations described in the chemical literature. 1H-pyridin-(2E)-ylidene and related N-donor ligands (Figure 1) have
structural features and catalytic activity of complexes containing polydentate NHC ligands.[1,2] This interest toward
been described recently and their coordination chemistry and catalytic chemistry investigated.
[1]
A related class of
chelating NHCs is due not only to the formation of more stable metal complexes, but also to the evidence that they provide
compound can be derived from norharman, a -carboline, that has wide biological relevance, but no metal coordination
interesting features that can fine tune the topological properties such as steric hindrance, bite angles, chirality and fluxional
chemistry has been reported. Here we describe the preparation of norharman derived ligands and their metal complexes. IR
behaviour.
spectroscopic and X-ray structural data (Figure 2) indicate that this class of ligand is a greater electron-donor than the Nheterocyclic carbenes.[2,3] Preliminary catalytic data will also be presented.
Recently we described a new methodology for the synthesis of novel hydrophilic pincer carbene ligand precursors
based on 1,2,4-triazole and imidazole rings, {H2C(HTzR)2}, {H2C(HImR)2} (R = PrSO3 or EtCOO).[3] The related carbenesilver(I) complexes were synthesized by reaction between the triazolium or imidazolium species with Ag 2O; in these
metallacycles, of general formula {Na2[H2C(TzR)2]2Ag2} and {Na2[H2C(ImR)2]2Ag2}, every silver atom is coordinated to
two triazolin- or imidazolin-2-ylidene rings, belonging to two different dicarbene units. Moreover we have reported the
synthesis of trimetallic carbene complexes of general formula {Ag3[HB(ImR)3]2} (R = Bn, Mes and tBu), which were
successfully employed, as carbene transfer reagents, in the synthesis of related Au(I) complexes by transmetallation; the
Ag(I) complexes also proved to be active catalysts in the Sonogashira reaction. [4] At the present we are developing the
chemistry of some new water soluble zwitterionic mono-NHC ligands and of the related Ag(I) and Au(I) carbene
complexes {(Im1R,3R)MCl} (M = Ag or Au; R = PrSO3 or CH2COOR′)[5] (Figure 1).
Figure 1. 1H-pyridin-(2E)-ylidene and related N-donor ligands
Figure 2. X-Ray diffraction of lithium with two molecules of ligand, iodine and THF
References
[1]
Figure 1
Shi., Q.; Thatcher, R. J.; Slattery, J.; Sauari, P. S.; Whitwood, A. C.; McGowan, P. C.; Douthwaite, R. E. Chem. Eur. J. 2009, 48, 2185.
Doster, M. E.; Johnson, S.A. Angew. Chem. Int. Ed. 2009, 48, 2185. Doster, M. E.; Hatnean, J. A.; Jeftic, T.; Modi, S.; Johnson, S. A. J.
Am. Chem. Soc., 2010, 132, 11923.
References
[2]
Tolman, C. A. Chem. Rev. 1977, 77, 313.
[1]
Mata, J. A.; Poyatos, M.; Peris, E. Coord. Chem. Rev. 2007, 251, 841.
[3]
Gusev, D. G. Organometallics 2009, 28, 763.
[2]
Corberán, R.; Mas-Marzá, E.; Peris, E. Eur. J. Inorg. Chem. 2009, 1700.
[3]
Papini, G.; Pellei, M.; Gioia Lobbia, G.; Burini, A.; Santini, C. Dalton. Trans. 2009, 35, 6985.
[4]
Biffis, A.; Gioia Lobbia, G.; Papini, G.; Pellei, M.; Santini, C.; Scattolin, E.; Tubaro, C. J. Organomet. Chem. 2008, 693, 3760.
[5]
Santini, C.; Pellei, M.; Gioia Lobbia, G.; Morresi, B.; Papini, G.; Marinelli, M. unpublished results.
POSTERS
POSTERS
Poster 57
Poster 58
Nitrous Oxide Activation by Dinuclear Ru Complexes
1-(4-nitritobutyl)-3-methylimidazolium chloride as a new, green and efficient
nitrosating reagent
Alexander Tskhovrebov* and Kay Severin
Hassan Valizadeh* and Hamid Gholipour
Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
*[email protected]
Department of Chemistry, Faculty of Sciences, Azarbaijan University of Tarbiat Moallem, Tabriz
*[email protected]
Nitrous oxide’s role in ozone depletion and its greenhouse effect has stimulated a lot of interest in activation of this
kinetically inert molecule.[1] In addition, N2O is an appealing oxidant due to its thermodynamic potency and
environmentally friendly nature (the only by product in oxygen atom transfer reactions is N 2).[2]
A new ionic liquid 1-(4-nitritobutyl)-3-methylimidazolium chloride (IL-ONO) was synthesized[1] and used as a
convenient nitrosonium source in several reactions including N-nitrosation, electrophilic aromatic nitrosation and -
Recently, we discovered that dinuclear Ru complexes are able to activate N2O at room temperature (see picture). NMR
oximination of ketones. Various nitrosating agents such as nitrous acid,[2] alkyl nitrites,[3] nitrosyl salts,[4] Fremy’s salt,[5]
spectroscopic and crystallographic analyses show that the Ru complexes mediate a rupture of the N-O bond to give Ru-
polymer-supported nitrosation reagent[6] and [NO+·Crown·H(NO3)2-][7] have been reported. In this work we wish to report
dinitrogen complexes along with autoxidation products.
the nitrite functionalized ionic liquid as a new reagent for efficient nitrosation reaction.
IL-ONO, HCl, H2O, 0 oC
R1R2NH
or IL-ONO, AcOH, CH2Cl2, r.t.
R1R2N-N=O
Scheme 1. N-nitrosation of secondary amines using IL-ONO.
NO
IL-ONO, HCl
R1
MW, Solvent-free
r.t , 1-3.5 min
R1
Scheme 2. MW-promoted solvent-free C-nitrosation using IL-ONO.
O
O
R2
R1
IL-ONO, HCl
r.t
R2
R1
R2= H or COR3
NOH
Scheme 3. Synthesis of oximinoketones using IL-ONO.
In conclusion, IL-ONO acts as an excellent alternative reagent for the nitrosation process. Easy and clean work-up and
References
[1]
Codispoti, L. A. Science, 2010, 327, 1339.
[2]
Tolman, W. B. Angew. Chem. Int. Ed. 2010, 49, 1018.
high yields make these methods attractive for organic synthesis.
References
[1]
Valizadeh, H.; Shomali, A. Dyes Pigments. 2010, doi: 10.1016/j.dyepig. 11.010.
[2]
(a) Sheriner, R. L.; Reynold, T. L.; Fuson, C.; Curtin, D. Y.; Morrill, T. C. “The Systematic Identification of Organic Compounds” John
Wiley & Sons, 1980, 6th edn, 220-223. (b) Le, Z.-G.; Chen, Z.-C.; Hu, Y.; Zheng, Q.-G. Synthesis 2004, 2809.
[3]
Wagner, R. B.; Zook, H. D. “Synthetic Organic Chemistry” John Wiley & Sons, New York. 1953, 739-745.
[4]
Graham, A.; Williams, D. L. H. J. Chem. Soc. Perkin Trans. 1992, 2, 747.
[5]
Castedo, L.; Riguera, R.; Vezquez, M. P. J. Chem. Soc. Chem. Commun. 1983, 301.
[6]
Lardy, C.; Tournier, L.; Prunier, M.; Valeur, E. Tetrahedron Lett. 2010, 51, 2277.
[7]
Zolfigol, M. A.; Zebarjadian, M. H.; Chehardoli, G.; Keypour, H.; Salehzadeh, S.; Shamsipur, M. J. Org. Chem. 2001, 66, 3619.
Poster 59
Poster 60
[bmim]NO2/H3BO3 as a new reagent for MW-promoted solvent-free synthesis of some
Toward immobilized, photocatalytically active hydrogenase mimics
1H-Benzotriazole derivatives
Bart van den Bosch,* Jarl Ivar van der Vlugt and Joost N.H. Reek
Hassan Valizadeh* and Hamid Gholipour
Supramolecular Catalysis, van `t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam,
e-mail: [email protected], website: http://www.science.uva.nl/research/imc/HomKat
Department of Chemistry, Faculty of Sciences, Azarbaijan University of Tar biat Moallem, Tabriz
*[email protected];
*[email protected]
In order to replace rapidly depleting, carbon-containing fossil fuels as mankind’s primary energy source, there is an
Task-specific nitrite ionic liquid ([bmim]NO2) was used as a reagent for the efficient synthesis of some 1Hbenzotriazole derivatives from functionalized 1,2-diaminobenzenes using H3BO3 under microwave irradiation conditions.
Benzotriazoles are of continuing interest for chemists and biologists as an important class of heterocyclic compounds.
Indeed, benzotriazole is a key structural fragment of a number of natural compounds, [1] vitamins (for example, B12)[2] and
biologically active compounds exhibiting herbicidal, [3] insecticidal,[4] acaricidal[5] and other activities. The commonly used
method for the preparation of benzotriazoles involves the diazotation reaction of 1,2-diaminobenzenes.[6] The alternative
method is cycloaddition of azides with arynes with limited examples having inconvenience in generating the arynes.[7]
example of converting the light of the sun into chemical energy is provided by nature’s photosynthesis. Mimicking the
natural photosynthesis enzymes might lead to the development of devices that are able to capture the energy of the sun and
store this in molecules, such as dihydrogen. Recently, supramolecular assembly A, which is capable of photocatalytic
reduction of protons to dihydrogen, has been developed in our group. [1] This Fe2-Hydrogenase mimic consists of the bioinspired Fe-Fe cluster (1) linked to different zinc-metallated porphyrins (2 and 3) via a supramolecular linker (4). In this
triad, the porphyrins act as photosensitizers. Remarkably, this assembly only showed photocatalytic activity when two
Ionic liquids are a powerful alternative to conventional molecular organic solvents or catalysts due to their particular
properties, such as undetectable vapor pressure, wide liquid range, as well as the ease of recovery and reuse. Because of the
ionic nature of ILs, these compounds absorb very efficiently MW irradiation and can increase the rate of the organic
reactions.
different porphyrins were employed. Upon irradiation of assembly A in the presence of sacrificial proton- and electron
donors, up to five equivalents of dihydrogen with respect to the assembly were generated. The goal of our current research
is to immobilize assembly A on a glass surface by means of spin coating and/or drop casting, and to obtain more insight in
fundamental proton-reduction mechanisms.
N NOH
NH2
N
[Bmim]NO2/H3BO3
N
solvent-free, MWI
NH2
R
increasing interest to new ways of harvesting solar energy in order to convert this into chemical energy. An intriguing
R
NH2
R= H, Cl, Me, NO2
R
N
H
1H-Benzotriazole
Scheme 1.Solvent-free synthesis of some 1H-Benzotriazole derivatives using [Bmim]NO2/H3BO3.
In conclusion nitrite-functionalized ionic liquid is an effective reagent and catalyst for the synthesis of 1Hbenzotriazole from 1,2-diaminobenzenes under MWI conditions. The advantages of the present protocol are shorter
reaction times, mild reaction conditions and good yields. The present convenient method is attractive to the existing
X-ray diffraction studies revealed assembly A to stack in such a way that a nanoporous material is formed in the solid state.
This nanoporous material might facilitate diffusion of protons and/or electrons through the catalyst film, resulting in a large
methods for the synthesis of 1H-benzotriazoles.
surface area at which proton reduction can take place. Therefore, a relatively high photocatalytic activity in the solid state
References
can be expected. In this contribution, the immobilization of assembly A, in order to increase the TON will be discussed.
[1]
Katritzky, R.; Belyakov, S. A. Aldrichim. Acta 1998, 31, 35.
Furthermore, the ability of the heterogenized catalyst to perform photocatalysis in aqueous solutions is investigated.
[2]
Krishnamurthy, M.; Phaniraj, P. Dogra, S. K. J. Chem. Soc., Perkin Trans. 2 1986, 1917.
[3]
Diehl, R. E.; Kendall, R. V. US Patent, 4086242, 1978 (Chem.Abstr., 1978, 89, 109512g).
[4]
Diehl, R. E.; Kendall, R. V. Belg. Patent, 853179, 1978 (Chem.Abstr., 1978, 88, 190843q).
[5]
Takeo, Fumio, H.; Hajime, I.; Rieko, M. Jpn. Patent, 78121762,1978 .
References
[6]
(a) Chan, M. S.; Hunter, W. E. U.S. Patent 4299965, 1981; (b) Muir, J. C.; Pattenden, G.; Ye, T. Tetrahedron Lett. 1998, 39, 2861.
[1]
[7]
Kitamura, T.; Fukatsu, N.; Fujiwara, Y. J. Org. Chem. 1998, 63, 8579.
Acknowledgements Financial support from NWO-CW (ECHO-grant) is acknowledged.
A. M. Kluwer, R. Kapre, F. Hartl, M. Lutz, A. L. Spek, A. M. Brouwer, P. W. N. M. van Leeuwen, J. N. H. Reek, PNAS, 2009, 26,
10460.
POSTERS
POSTERS
Poster 61
Poster 62
Molybdenum and tungsten complexes for heterogeneous oxidation catalysis
Synthesis of helical phosphorus derivatives
Maria Vasconcellos Dias,a* Newton Dias Filho,b Paula Ferreira,c Maria José Calhordaa
Keihann Yavari,* Arnaud Voituriez, Angela Marinetti
a
b
c
Dept. de Química e Bioquímica,FCUL, Campo Grande, 1749-016 Lisboa, Portugal
Institut de Chimie des Substances Naturelles, CNRS, Bat 29, Av. de la Terrasse, 91198, Gif-Sur-Yvette, France
FE Ilha Solteira (UNESP), DFQ, Av. Brasil centro, 56 CEP 15385-000, Ilha Solteira Brasil
*[email protected]
Dept. de Engenharia Cerâmica e do Vidro, CICECO, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
*[email protected]
Molecular scaffolds with helical chirality have been rarely used for building phosphorus ligands and catalysts. [1] Most
compounds of this class display a helical moiety with an appended phosphorus function. Notable exceptions are the
The wide variety of applications for Si-O-Si materials, namely inorganic compounds, such as silicates and
Tanaka’s helical phosphafluorenes where phosphorus is embedded into the helical structure itself. [2]
aluminosilicates, organometallic complexes, polymers, includes functional models with industrially importance. Silica
supported metal catalysts with a well-defined geometry led to a significant breakthrough in the past decade. The reaction of
functional surface groups SiOH with Cl(CH2)3Si(OEt)3 was the first step for obtaining new heterogeneous catalysts
containing Mo and W.[1] Functionalized organic bridges, such as C2H3N3S, can be immobilized on the second step of this
In this context, with the purpose of accessing unprecedented chiral auxiliaries for organo- and organometallic catalysis,
we have targeted a new series of phospha-helicenes of the general formula shown hereafter, where the helical sequence of
aromatic rings ends with a phosphole unit.
reaction, giving a different elemental richness to the catalysts, and allowed to react with the complexes [Mo(3CH5)Br(CO)2(CH3CN)2] and [MX2(CO)3(CH3CN)2] (M=Mo, W and X=I, Br). After substituting the two labile CH3CN
groups, a whole new family of heterogeneous and homogeneous catalysts was obtained [2] (Figure 1). These new materials,
as well as their homogeneous counterparts were characterized by different techniques and tested as precursors for oxidation
catalysis of cis-cyclooctene, styrene, geraniol, 1-octene, cis-3-hexen-1-ol, trans-2-hexen-1-ol e S(-)-limonene in the
presence of t-butylhydroperoxide (TBHP). Immobilizing [Mo(3-C3H5)Br(CO)2(C2H3N3S)2] into silica or silsesquioxanes [3]
improves the selectivity for the conversion into the epoxide from 70% to 100% or 99,9%, respectively.
Figure 1
An efficient synthetic method as well as the spectral and structural characterizations for these compounds will be
presented.
Acknowledgment MVD (SFRH/BD/37690/2007) thanks FCT for financial support
References
References
[1]
Jain, K. R.; Kühn, F. E. Dalton Trans., 2008, 2221.
[2]
Dias, M. V.; Nunes, C. D.; Vaz, P. D.; Ferreira, P.; Brandão, P.; Félix, V.; Calhorda, M. J. J. Catal., 2008, 256, 301.
[3]
Dias Filho, N. L. Encyclopedia of Surface and Colloid Science 2ed. New York: Taylor & Francis, 2006, 229.
[1]
(a) Reetz, M. T.; Sostmann, S. J. Organomet. Chem. 2000, 603, 105; (b) Graule, S.; Rudolph, M.; Vanthuyne, N.; Autschbach, J.;
Roussel, C.; Crassous, J.; Réau, R. J. Am. Chem. Soc. 2009, 131, 3183; (c) Krausová, Z.; Sehnal, P.; Bondzic, B. P.; Chercheja, S.;
Eilbracht, P.; Stará, I. G.; Šaman, D.; Starý, Eur. J. Org. Chem. 2011, 3849, and references therein.
[2]
Fukawa, N.; Osaka, T.; Noguchi, K.; Tanaka, K. Org. Lett. 2010, 12, 1324.
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Space for spots of EJIC
Index of Participants
Name
E-Mail
Poster
Name
E-Mail
Abbotto Alessandro
[email protected]
speaker
Coppi Donato Ivan
[email protected]
18
Albinati Alberto
[email protected]
speaker
Cornelio Benedetta
[email protected]
19
Andersson Pher
[email protected]
speaker
Curcio Massimiliano
[email protected]
Antonucci Daniela
[email protected]
1
Dalla Cort Antonella
[email protected]
Aversa Manuela
[email protected]
2
Daniele Valeria
[email protected]
Baron Marco
[email protected]
Dell'Acqua Monica
[email protected]
Barozzino C. Gabriella
[email protected]
3
Diez Martinez Alba
[email protected]
Bartocci Silvia
[email protected]
4
Diomedi Simone
[email protected]
Basato Marino
[email protected]
Drost Ruben
[email protected]
21
Benedetti Erica
[email protected]
Durini Marco
[email protected]
22
Benedetti Michele
[email protected]
Fasana Andrea
[email protected]
Berrocal Josè Augusto
[email protected]
6
Ferretti Francesco
[email protected]
Bèthegnies Aurélien
[email protected]
7
Figliolia Rosario
[email protected]
Bianchini Giulio
[email protected]
8
Fiore Marco
[email protected]
Birrozzi Agnese
[email protected]
Fratoni Davide
[email protected]
Bochmann Manfred
[email protected]
Georgiana Maties
[email protected]
Bordoni Silvia
[email protected]
Gjoka Blerina
[email protected]
24
Borsini Elena
[email protected]
Gottardo Marina
[email protected]
25
Braunstein Pierre
[email protected]
Hossaini Sadr Moayad
[email protected]
Bruschini Michele
[email protected]
10
Hindson Karen
[email protected]
Cantoni Giulia
[email protected]
11
Intrieri Daniela
[email protected]
Carrara Claudio
[email protected]
12
Jadhav Milind Suresh
[email protected]
Castano Brunilde
[email protected]
13
Jagenbrein Martin
[email protected]
29
Cauteruccio Silvia
[email protected]
14
Jullien Hélène
[email protected]
30
Chay Rogerio S.
[email protected]
Kozinets Ekaterina M.
[email protected]
Cipolletti Roberto
[email protected]
Krause Norbert
[email protected]
speaker
Clot Eric
[email protected]
speaker
Lacour Jérôme
[email protected]
speaker
Coccia Francesca
[email protected]
15
Lanza Arianna
[email protected]
32
Coletti Alessia
[email protected]
16
Lega Matteo
[email protected]
33
Connolly Craig
[email protected]
17
Lelii Camilla
[email protected]
34
Coogan Michael P.
[email protected]
speaker
Lentini Sara
[email protected]
35
5
speaker
9
speaker
Poster
20
23
26-27
28
31
Leo Virginia
[email protected]
Ruffo Francesco
[email protected]na.it
Licandro Emanuela
[email protected]
Russotto Eleonora
[email protected]
Licini Giulia
[email protected]
Salomone Antonio
[email protected]
50
Llobet Antoni
[email protected]
Santos Hurtado Carina
[email protected]
51
Luzyanin Konstantin V.
[email protected]
Savini Arianna
[email protected]
52
Macchioni Alceo
[email protected]
Serratrice Maria
[email protected]
53
Maidich Luca
[email protected]
Silarska Ewelina
[email protected]
54
Maiorana Stefano
[email protected]
Solinas Gavino
[email protected]
55
Marek Ilan
[email protected]
Soltani Behzad
[email protected]
Mari Margherita
[email protected]
Sorana Federico
[email protected]
Marinaro Mario
[email protected]
Suberg Marcus
[email protected]
Marsili Laura
[email protected]
Sun Licheng
[email protected]
Meduri Angelo
[email protected]
38
Tabacaru Aurel
[email protected]
Mellone Irene
[email protected]
39
Timokhin Ivan
[email protected]
Mignini Pasqualina
[email protected]
Titov Aleksei
spor4e[email protected]
Molteni Roberto
[email protected]
Tomé Cátia
[email protected]
Monakhov Kirill Yu.
[email protected]
Trasatti Andrea
[email protected]
56
Monari Magda
[email protected]
Tskhovrebov Alexander
[email protected]
57
Morin Aurélie
[email protected]
Tubaro Cristina
[email protected]
Ngoune Jean
[email protected]
Valizadeh Hassan
[email protected]
O'Connor Crystal
[email protected]
Van Den Bosch Bart
[email protected]
60
Orbisaglia Serena
[email protected]
Vasconcellos Dias Maria
[email protected]
61
Perfetto Alessandra
[email protected]
Volpe Andrea
[email protected]
Pettinari Riccardo
[email protected] it
Ward Thomas R.
[email protected]
Pietropaolo Emanuela
[email protected]
Yavari Keihann
[email protected]
Polukeev Alexey V.
[email protected]
Properzi Roberta
[email protected]
Ragaini Fabio
[email protected]
Regis Réau
[email protected]
Ricci Simone
[email protected]
47
Rocchigiani Luca
[email protected]
48
Rocha Bruno G. M.
[email protected]
49
speaker
36
37
speaker
40
41
42
43
44-45
46
speaker
Index of Participants
speaker
58-59
speaker
62
BOOK OF ABSTRACTS SPONSORED BY

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