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Download The The Final Program The Final Program for this Symposium was modified from that presented in the Book of Abstracts mainly due to the unforeseen incidence of the coronavirus in late January, 2020. We are grateful to the distinguished scientists who were able to take the place of those who were unable to come, and we regretted the absence of the distinguished scientists who had planned until the last hours to be with us. The SCHEDULE that is posted on this web site is the Final Schedule. That which is in the Book of Abstracts is the schedule that was expected to be the final schedule two weeks prior to the event. Strongly Donating 1,2,3-Triazole-Derived Carbenes for Metal-Mediated Redox Catalysis Simone Bertini, Matteo Planchestainer, Francesca Paradisi, Martin Albrecht Department of Chemistry & Biochemistry, University of Bern, CH-3012 Bern, Switzerland [email protected] Triazole-derived N-heterocyclic carbenes have become an attractive addition to the family of NHC ligands, in parts because their versatile and functional group-tolerant synthesis through click- chemistry,1 and in other parts because of their stronger donor properties to transition metals when compared to ubiquitous Arduengo-type carbenes.2. We have been particularly attracted recently by the high robustness of these ligands towards oxidative and reductive conditions, which provides appealing opportunities for challenging redox catalysis. We have exploited these properties for example for developing iridium complexes as highly active and molecular water oxidation catalysts.3 Here we will present our efforts to use triazole-derived carbenes to enable 1st row transition metals as catalytically competent entities. Incorporation of additional (hard) donor sites is benefical for this purpose and is greatly facilitated by the insensitivity of the click reaction to such functionalities. Here we will discuss new advances in redox catalysis including CO2 and proton reduction with first row transition metals carbene systems. Moreover, we have expanded this carbene bonding to natural systems involved in redox processes.4 References 1. Kolb, H. C.; Finn, M. G.; Sharpless, K. B. Click Chemistry: Diverse Chemical Function from a Few Good Reactions. Angew. Chem. Int. Ed. 2001, 40 (11), 2004–2021. 2. Vivancos, Á.; Segarra, C.; Albrecht, M. “Mesoionic and Related Less Heteroatom-Stabilized N-Heterocyclic Carbene Complexes: Synthesis, Catalysis, and Other Applications” Chem. Rev. 2018, 118, 9493–9586. 3. Woods, J. A.; Lalrempuia, R.; Petronilho, A.; McDaniel, N. D.; Müller-Bunz, H.; Albrecht, M.; Bernhard, S. Carbene Iridium Complexes for Efficient Water Oxidation: Scope and Mechanistic Insights. Energy Environ. Sci. 2014, 7, 2316–2328. 4. Planchestainer, M.; Ségaud, N.; Shanmugam, M.; McMaster, J.; Paradisi, F.; Albrecht, M. “Carbene in Cupredoxin Protein Scaffolds: Replacement of a Histidine Ligand in the Active Site Substantially Alters Copper Redox Properties” Angew. Chem. Int. Ed. 2018, 57, 10677– 10682 1 Martin Albrecht Department of Chemistry & Biochemistry, University of Bern Freiestrasse 3 3012 Bern, Switzerland Email: [email protected] Web: http://albrecht.dcb.unibe.ch Twitter @albrecht_lab Education 2002 – 2003 Postdoctoral Researcher Ciba SC, Basel (CH), within R&D Coating Effects 2001 –2002 Postdoctoral Research Associate, Yale University (USA) with Prof. R. H. Crabtree 1996 – 2000 Ph.D Utrecht University (NL) with Prof. G. van Koten 1991 – 1996 M.Sc. in Chemistry, University of Bern (CH); thesis work with T. R. Ward / A. Ludi Positions 2015 – present Full Professor of Inorganic Chemistry, University of Bern (Switzerland) 2013 – 2015 Vice-Principal of Research and Innovation, UCD Faculty of Science 2009 – 2015 Full Professor of Inorganic Chemistry, University College Dublin (Ireland) 2003 – 2009 Alfred Werner Assistant Professor, University of Fribourg (CH), Principal Investigator Awards & Invitations 2017 GIAN fellow (Indian Minstery of Human Resource Development) 2015 CATSA Eminent Visitor Award (Catalysis Society of South Africa) 2014 ERC Consolidator Grant 2013 Humboldt Fellow (Friedrich Wilhelm Bessel Research Award of A.v.H. Foundation) 2011 Fellow of the Royal Society of Chemistry (FRSC) 2008 Visiting Professor University of Otago (New Zealand) 2007 ERC starting grant 2003 Alfred Werner Assistant Professorship 2001 Backer prize of the KNCV (Royal Dutch Chemical Society) Research Interests Ligand design, homogeneous catalysis, N-heterocyclic carbene metal complexes, redox catalysis, mesoionic C- and N-donor ligands, artificial metalloenzymes Representative Publications 1,2,3-Triazolylidenes as Versatile Abnormal Carbene Ligands for Late Transition Metals P. Mathew, A. Neels, M. Albrecht, J. Am. Chem. Soc. 2008, 130, 13534–13535 Carbene in Cupredoxin Protein Scaffolds: Replacement of a Histidine Ligand in the Active Site Substantially Alters Copper Redox Properties M. Planchestainer, N. Ségaud, M. Shanmugam, J. McMaster, F. Paradisi, M. Albrecht, Angew. Chem. Int. Ed. 2018, 57, 10677–10682 NHC-based Iridium Catalysts for Hydrogenation and Dehydrogenation of N-Heteroarenes in Water under Mild Conditions A. Vivancos, M. Beller, M. Albrecht, ACS Catal. 2018, 8, 17–21 Mesoionic and Related Less Heteroatom-Stabilized N-Heterocyclic Carbene Complexes: Synthesis, Catalysis, and Other Applications A. Vivancos, C. Segarra, M. Albrecht, Chem. Rev. 2018, 118, 9493–9586. 2 Carbenes as powerful transition metal surrogates Guy Bertrand UCSD-CNRS Joint Research Laboratory, Department of Chemistry, University of California, San Diego, La Jolla, California 92093-0358, USA [email protected] It has been previously demonstrated that stable singlet electrophilic carbenes can behave as metal surrogates in the activation of small molecules and enthalpically strong E-H bonds,1 but it was believed that these activations only proceed through an irreversible activation barrier. We will show that, as it is the case with transition metals, the steric environment can be used to promote a reductive elimination at a carbon center.2 Along this line, we will show that stable bicyclic (alkyl)(amino)carbenes3 allow for the stoichiometric carbonylation of ortho-quinones, the catalytic version being hampered by the reaction of the carbene with the quinones. However, the use of a bulky cyclic (alkyl)(amino)carbenes4 avoids this quenching, and thus allows for the catalytic carbonylation reaction into the corresponding cyclic carbonates.5 H/D exchange at formyl groups is the most direct approach for the synthesis of deuterated aldehydes. Until now, only platinum-group metal complexes were known to catalyze this transformation, with significant substrate scope limitations. We have found that mesoionic carbenes6 catalyze the H/D exchange of aryl, alkenyl and alkyl aldehydes in high yields and deuterium incorporation levels using deuterated methanol as an affordable D source.7 References 1. Frey, G. D.; Lavallo, V.; Donnadieu, B.; Schoeller, W. W.; Bertrand, G. “Facile Splitting of Hydrogen and Ammonia by Nucleophilic Activation at a Single Carbon Center.” Science 2007, 316, 439-441. 2. D. R. Tolentino, S. E. Neale, C. J. Isaac, S. A. Macgregor, M. K. Whittlesey, R. Jazzar, G. Bertrand, “Reductive Elimination at Carbon under Steric Control” J. Am. Chem. Soc. 2019, 141, 9823-9826. 3. Tomás-Mendivil, E.; Hansmann, M. M.; Weinstein, C. M.; Jazzar, R.; Melaimi, M.; Bertrand, G. “Bicyclic (Alkyl)(amino)carbenes (BICAACs): Stable Carbenes more Ambiphilic than CAACs” J. Am. Chem. Soc. 2017, 139, 7753-7756. 4. Melaimi, M.; Jazzar, R.; Soleilhavoup, M.; Bertrand, G. “Cyclic (Alkyl)(Amino)Carbenes (CAACs): Recent developments” Angew. Chem. Int. Ed. 2017, 56, 10046-10068. 5. Tomás-Mendivil, E.; Tolentino, D. R.; Peltier, J. R.; Jazzar, R.; Bertrand, G. unpublished 2019 6. Guisado-Barrios, G.; Soleilhavoup, M.; Bertrand, G. “1H‑1,2,3-Triazol-5-ylidenes: Readily Available Mesoionic Carbenes” Acc. Chem. Res. 2018, 51, 3236-3244. 7. Liu, W.; Zhao, L. L.; Melaimi, M.; Cao, L.; Xu, X.; Bouffard, J.; Bertrand, G.; Yan, X. unpublished 2019 3 CURRICULUM VITAE – Guy Bertrand Professor of Chemistry Director of the UCSD-CNRS Joint Research Laboratory, Department of Chemistry, University of California, San Diego, La Jolla, California 92093- 0358, United States Tel: 001 (858) 534-5412 Email: [email protected] Homepage: http://bertrandgroup.ucsd.edu Scientific Vita Since 2012 University of California San Diego, Distinguished Professor, Department of Chemistry and Biochemistry. 2002-2012 University of California Riverside, Distinguished Professor, Department of Chemistry. 1998-2005 Director of the Laboratoire d'Hétérochimie Fondamentale et Appliquée at the University Paul Sabatier (Toulouse, France) 1988-1998 Director of Research CNRS, Laboratoire de Chimie de Coordination (Toulouse, France) Research Field Stabilization of highly reactive species, stable carbenes and their uses as ligands for transition metals, as organocatalysts, and in material sciences Selected Awards and Recognition 2004 Member the French Academy of Sciences 2006 Fellow of the American Association for Advancement of Science 2010 Sir Ronald Nyholm Lectureship and Medal of the RSC 2010 Grand Prix Le Bel of the French Chemical Society 2013 Chevalier de la Legion d’Honneur 2014 ACS Award in Inorganic Chemistry 2015 Senior Humboldt Research Award, Reinvitation 2016 Sir Geoffrey Wilkinson Award of the RSC 2017 Sacconi Medal of the Italian Chemical Society 2018 Named “Distinguished Visiting Professor” at Tsinghua University (China) 2018
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