Radical Arylalkoxycarbonylation of 2-Isocyanobiphenyl with Carbazates: Dual C-C Bond Formation toward Phenanthridine-6-carboxylates

A sequential oxidative radical alkoxycarbonylation and aromatization of 2-isocyanobiphenyl with carbazates was developed to furnish phenanthridine-6-carboxylates. Various functional groups such as methoxy, chloro, fluoro, trifluoromethoxy, and trifluoromethyl groups were tolerated well under the reaction conditions. The sequential radical addition-cyclization strategy represents a practical route to access phenanthridine-6-carboxylates.