Asymmetric addition of hydrazones as alkyl carbanion equivalents with aryl imines in water

Abstract

An asymmetric umpolung addition of hydrazones as alkyl carbanion equivalents with imines in water was developed under the catalysis of a Ru–diamine–diphosphine system in the presence of crown ether. Chiral amines were obtained in moderate to good yields with high enantioselectivities. The usage of water afforded better yields and enantioselectivities than that of organic solvents, which provided a new method for green and sustainable synthesis of chiral amines.