Enantioselective Alkynylation of 2-Trifluoroacetyl Imidazoles Catalyzed by Bis-Cyclometalated Rhodium(III) Complexes Containing Pinene-Derived Ligands
作者:Yu Zheng、Klaus Harms、Lilu Zhang、Eric Meggers
DOI:10.1002/chem.201602372
日期:2016.8.16
Chiral rhodium(III) complexes containing two cyclometalating 2‐phenyl‐5,6‐(S,S)‐pinenopyridine ligands and two additional acetonitriles are introduced as excellent catalysts for the highly enantioselective alkynylation of 2‐trifluoroacetyl imidazoles. Whereas the ligand‐based chirality permits the straightforward synthesis of the complexes in a diastereomerically and enantiomerically pure fashion,
Combining single electron transfer between a donor substrate and a catalyst‐activated acceptor substrate with a stereocontrolled radical–radical recombination enables the visible‐light‐driven catalytic enantio‐ and diastereoselective synthesis of 1,2‐amino alcohols from trifluoromethyl ketones and tertiary amines. With a chiral iridium complex acting as both a Lewis acid and a photoredox catalyst,