Catalytic Enantioselective Silylation of N?Sulfonylimines: Asymmetric Synthesis of α?Amino Acids from CO_2 via Stereospecific Carboxylation of α?Amino Silanes

摘要

A catalytic enantioselective silylation of N-tertbutylsulfonylimines using a Cu?secondary diamine complex was demonstrated. The resulting optically active α-amino silanes could be carboxylated under a CO_2 atmosphere (1 atm) to afford the corresponding α-amino acids in a stereoretentive manner. This two-step sequence provides a new synthetic protocol for optically active α-amino acids from gaseous CO_2 and imines in the presence of a catalytic amount of a chiral source.