Carbene-catalyzed [3 + 2 + 1] annulation via C–N radical coupling of iminyl radicals and ketyl radicals

An NHC-catalyzed [3 + 2 + 1] annulation of vinyl azides, aldehydes, and Togni’s reagents was reported. The cascade involves NHC-catalyzed SET redox transformation, denitrogenated radical migration, C–N radical coupling, and defluorinated cyclization.