Iridium‐Catalyzed Enantioselective Hydrogenation of Olefins

Abstract

Abstract Cationic iridium complexes with chiral P,N‐ligands and tetrakis[3,5‐(trifluoromethyl)phenyl]borate (BAr F ) as the counterion are efficient homogeneous catalysts for the enantioselective hydrogenation of olefins. The complexes are readily prepared, air‐stable, and easy to handle. In contrast to chiral rhodium‐ and ruthenium‐phosphine catalysts, they do not require the presence of a polar coordinating group near the CC bond. In the hydrogenation of unfunctionalized arylolefins, high enantioselectivities of >95% ee with turnover numbers of up to 5000 and turnover frequencies of >5000 h −1 have been achieved.