Helical chiral N‐heterocyclic carbene ligands in enantioselective gold catalysis

• Published in: Chemistry – A European Journal
• Main Authors: Pallova, Lenka, Abella, Laura, Jean, Marion, Vanthuyne, Nicolas, Barthes, Cécile, Vendier, Laure, Autschbach, Jochen, Crassous, Jeanne, Bastin, Stéphanie, César, Vincent
• Other Authors: Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry Buffalo, University at Buffalo SUNY (SUNY Buffalo), State University of New York (SUNY)-State University of New York (SUNY), Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), National Science Foundation (Grant CHE-1855470), ANR-16-CE07-0019,HEL-NHC,Carbènes N-hétérocycliques (NHC) hélicéniques: synthèse, structure, propriétés photophysiques et activité catalytique(2016)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: Helicenes; N-heterocyclic; Carbenes; Gold; Asymmetric catalysis; Chirality; [CHIM.COOR]Chemical Sciences/Coordination chemistry; IPY
• Online Access: https://hal.science/hal-03575284; https://hal.science/hal-03575284/document; https://hal.science/hal-03575284/file/Pallova,%20Helical%20chiral%20N-heterocyclic%20carbene,%202022.pdf; https://doi.org/10.1002/chem.202200166

International audience The first chiral helicene-NHC gold(I) complexes efficient in enantioselective catalysis were prepared. The L-shaped chiral ligand is composed of an imidazo[1,5-a]pyridin-3-ylidene (IPy) scaffold laterally-substituted by a configurationally stable [5]-helicenoid unit. The chiral information was introduced in a key post-functionalization step of a NHC-gold(I) complex bearing a symmetrical anionic fluoreno[5]helicene substituent, leading to a racemic mixture of complexes featuring three correlated elements of chirality, namely central, axial and helical chirality. After HPLC enantiomeric resolution, X-ray crystallography and theoretical calculations enabled structural and stereochemical characterization of these configurationally stable NHC-gold(I) complexes. The high potential in asymmetric catalysis is demonstrated in the benchmark cycloisomerization of N-tethered 1,6-enynes with up to 95:5 er.