Enantioselective Synthesis of β‐Amino Acids: TMS‐SAMP as a Chiral Ammonia Equivalent for the Aza Analogous Michael Addition to α,β‐Unsaturated Esters

Abstract

The N-silylated chiral amines TMS-SAMP and TMS-RAMP can be employed for stereoselective CN bond formation with enantiomeric excesses of 90-80%. In these reactions, the corresponding hydrazinoesters are formed initially, which are subsequently cleaved hydrogenolytically to give the desired β-amino acids 1. R = alkyl, R′ = Me, tBu.