Indolizy Carbene Ligand. Evaluation of Electronic Properties and Applications in Asymmetric Gold(I) Catalysis. Issue 36 (29th July 2021)

• Record Type: Journal Article
• Authors: Martinez, Thibaut; Vanitcha, Avassaya; Troufflard, Claire; Vanthuyne, Nicolas; Forté, Jérémy; Gontard, Geoffrey; Lemière, Gilles; Mouriès‐Mansuy, Virginie; Fensterbank, Louis
• Is Part Of: Angewandte Chemie international edition. Volume 60:Issue 36(2021)
• Page Start: 19879
• Page End: 19888
• Publication Date: 2021-07-29
• Subjects: asymmetric catalysis -- carbene -- DFT -- gold -- phosphine oxide; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202106142
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: We report herein a new family of carbene ligands based on an indolizine‐ylidene (Indolizy) moiety. The corresponding gold(I) complexes are easily obtained from the gold(I)‐promoted cyclization of allenylpyridine precursors. Evaluation of the electronic properties by experimental methods and also by DFT calculations confirms strong σ‐donating and π‐accepting properties of these ligands. Cationization of the gold(I) complexes generates catalytic species that trigger diverse reactions of (poly)unsaturated precursors. When armed with a methylene phosphine oxide moiety on the stereogenic center adjacent to the nitrogen atom, the corresponding bifunctional carbene ligands give rise to highly enantioselective heterocyclizations. DFT calculations brought some rationalization and highlighted the critical roles played by the phosphine oxide group and the tosylate anion in the asymmetric cyclization of γ‐allenols. Abstract : Au I complexes coordinated to the Indolizy ligand, a new carbene ligand that results from the gold‐promoted cyclization of a pyridyl‐allene were investigated. The electronic properties of the Indolizy ligand were analysed. The introduction of a stereogenic center in α‐position to the carbene center coupled to the introduction of a pending phosphine oxide group affords highly efficient and enantioselective Au I catalysts.