Copper-Catalyzed Tandem Cyclization/Direct C(sp)-H Annulation of Azide-Ynamides via α-Imino Copper Carbenes: Access to Azepino[2,3-:4,5-']diindoles.

A novel copper-catalyzed tandem cyclization/direct C(sp)-H annulation of phenyl azide-ynamides via α-imino copper carbenes has been developed, which provides a concise and flexible approach for the construction of a range of valuable azepino[2,3-:4,5-']diindoles in mostly good to excellent yields with high chemoselectivities. This tandem reaction also exhibits a broad substrate scope, excellent functional group tolerance, simple operation, and mild reaction conditions.