One-Pot Catalytic Synthesis of α-Tetrasubstituted Amino Acid Derivatives via In Situ Generation of N -Unsubstituted Ketimines.

A one-pot catalytic synthesis of α-tetrasubstituted amino acid derivatives via in situ generation of N -unsubstituted ketimines is reported. Because of the irreversible formation of N -unsubstituted ketimines, the yields were higher than those generated under the conventional one-pot reaction conditions. This process prevents the need to isolate unstable N -unsubstituted ketimines with alkyl substituents and streamlines the synthesis of highly congested α-amino acid derivatives.