Asymmetric hydrogenation of ketones with H2 and ruthenium catalysts containing chiral tetradentate S2N2 ligands

Abstract

Getting more for less: In the presence of H2 and a base, air- and moisture-tolerant RuII complexes catalyze the hydrogenation of ketones and aldehydes with excellent activity and chemoselectivity, and with enantioselectivity of up to 95 % under mild conditions. The ratio of substrate to catalyst can be lowered to 106:1. The reactions tolerate scale-up and can be carried out with almost no solvent. A base-free method is available for base-sensitive substrates. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.