“Cut-and-Sew” Reactions of β-Lactams via C–C Bond Activation

Transition metal-catalyzed "cut-and-sew" reactions offer an efficient approach to construct bridged and fused scaffolds; however, the substrates have been primarily restricted to cyclic ketones and activated cyclopropanes. Here we report the first cut-and-sew transformation between β-lactams and alkenes/alkynes via C-C bond activation. Diverse bridged and fused nitrogen-heterocycles are prepared using this method with good functional group tolerance. The synthetic utility is demonstrated in the unified and streamlined preparation of norbenzomorphan-containing bioactive compounds.