Visible-Light-Mediated Decarboxylative Tandem Carbocyclization of Acrylamide-Attached Alkylidenecyclopropanes: Access to Polycyclic Benzazepine Derivatives.

A visible-light-mediated decarboxylative tandem carbocyclization of acrylamide-tethered alkylidenecyclopropanes with phenyliodine(III) diacetate and various aliphatic acids has been reported in this paper. An alkyl radical in situ generated from phenyliodine(III) dicarboxylates upon visible-light irradiation catalyzed by fac-Ir(ppy)3 adds to the less hindered central carbon of alkylidenecyclopropane to initiate the tandem annulation, generating tetracyclic benzazepine derivatives in moderate to good yields with broad substrate scope under mild conditions.