A strategy for the Cα-umpolung of amides through the copper-catalyzed decarboxylation of 5-ethynyloxazolidine-2,4-diones was developed. Building on this, an asymmetric propargylic amination was achieved using primary and secondary amines as nucleophiles under cooperative catalysis of a chiral copper complex and a quinidine-derived bifunctional organocatalyst, affording a range of Cα-tetrasubstituted α-amino acid derivatives in high yields with excellent enantioselectivities. The synthetic utility of this protocol was demonstrated by late-stage modification of pharmaceuticals, large-scale reactions, and versatile derivatization of products.
Sun et al. (Thu,) studied this question.