To further understand the unique reactivity of iridium complexes for atom transfer C�H functionalization, a family of iridium(III)-bis(oxazolinyl)phenyl complexes were designed and synthesized. These complexes were found to catalyze the asymmetric insertion of donor/acceptor iridium carbenoids into activated C�H bonds. Low catalyst loadings (0.5 mol %) routinely lead to excellent reaction yields (74-99 %) and enantioselectivities (83-99 %). Density functional theory calculations provide compelling evidence that in these complexes the carbene binds to the iridium cis to the phenyl group of the bis(oxazolinyl)phenyl ligand. This finding is vital for understanding the observed stereochemical induction and is of particular significance in the field of enantioselective transition metal-catalysed atom transfer reactions utilizing oxazoline-X-oxazoline tridentate ligands, as previously employed stereochemical models for these ligand sets are based on the assumption that reactive ligands and Lewis bases bind trans to the central X ligand.

Experimental and computational studies on iridium(III)-bis(oxazolinyl)phenyl catalysts for enantioselective C-H functionalization

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.