Catalytic nucleophilic addition of terminal alkynes to α,β-unsaturated-γ-lactams

Abstract

A novel catalytic reaction has been developed for the nucleophilic addition of terminal alkynes to α,β-unsaturated-γ-lactams via a cyclic N-acyliminium ion intermediate. This simple reaction proceeds rapidly under mild conditions, and provided a practical approach for the synthesis of a wide range of 5-alkynyl-2-pyrrolidinones in moderate to good yields (45%–76%).