Lewis Acid Catalyzed Highly Stereoselective Domino-Ring-Opening Cyclization of Activated Aziridines with Enolates: Synthesis of Functionalized Chiral γ-Lactams

A highly enantio- and diastereoselective Lewis acid catalyzed S_N2-type ring opening followed by cyclization of aziridines with active methylene carbon nucleophiles to functionalized chiral γ-lactams in a domino fashion has been developed. γ-Lactams have been desulfonated and decarboxylated, providing pyrrolidone-3-carboxylate and N-tosylpyrrolidinone derivatives, respectively, in good yields.