Asymmetric Strecker reaction of ketoimines catalyzed by a novel chiral bifunctional N,N′-dioxide

A novel bifunctional N,N'-dioxide derived from L-prolinamide was employed to catalyze the enantioselective Strecker reaction of a range of N-tosyl ketoimines, and an effective additive was used to improve the reactivity (up to 99% yield) as well as the enantioselectivity (up to 91% ee). In addition, a rational transition state was proposed to elucidate the origin of chiral induction in which an S-adduct was produced.