Arylsulfonyl Radical Triggered 1,6-Enyne Cyclization: Synthesis of γ-Lactams Containing Alkenyl C-X Bonds.

Cascade radical cyclization of 1,6-enynes for the synthesis of biologically important γ-lactams containing alkenyl C-X bonds is reported. In these radical cascade processes, three new chemical bonds, including C-S, C-C, and C-X bonds, are formed in one step. The method is attractive and valuable due to its mild reaction conditions, broad substrate scope, and the importance of the corresponding γ-lactam products.