Catalytic Enantioselective Silylation of <i>N</i>‑Sulfonylimines: Asymmetric Synthesis of α‑Amino Acids from CO₂ via Stereospecific Carboxylation of α‑Amino Silanes

A catalytic enantioselective silylation of <i>N</i>-<i>tert</i>-butylsulfonylimines using a Cu–secondary diamine complex was demonstrated. The resulting optically active α-amino silanes could be carboxylated under a CO₂ 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 CO₂ and imines in the presence of a catalytic amount of a chiral source