Pd/Cu dual catalysis: highly enantioselective access to α-substituted α-amino acids and α-amino amides

Abstract

The asymmetric allylation of glycine iminoesters has been accomplished through a synergistic Pd/Cu catalyst system, affording a range of α-substituted α-amino acids in high yields and with excellent enantioselectivities (88 → 99% ee). The introduction of a Cu-P,N-metallocenyl complex-activated glycine iminoester to the chiral palladium-catalyzed allylic allylation process is crucial owing to its high reactivity and excellent enantioselectivities. Importantly, this Pd/Cu dual catalysis strategy can be used for the asymmetric allylic alkylation of prochiral glycine amide derivatives, which could be further utilized to synthesize biologically important vicinal diamines.