L-cysteine-derivatives in asymmetric synthesis: Preparation of two new chiral β-amino alcohols and their application in the enantioselective catalytic reduction of prochiral aromatic ketones with borane

Abstract

The optically active β-amino alcohols 1 and 2 derived from S-alkylated L-cysteine 3 and 4 respectively catalyze the enantioselective reduction of unsymmetrical ketones with borane. The resulting chiral secondary alcohols are obtained in high optical yields up to 100% under mild reaction conditions.