Phosphonium ylide catalysis through an oxidative quenching cycle has been developed for visible-light-driven C−H imidation of arenes and heteroarenes. The present protocol could be applied not only to trihalomethylative lactonization reactions involving trifluoromethyl, trichloromethyl, and tribromomethyl radicals but also to the first example of an organophotoredoxcatalyzed imidative lactonization reaction involving a nitrogencentered electrophilic radical species.

Phosphonium ylide catalysis through an oxidative quenching cycle has been developed for visible-light-driven C−H imidation of arenes and heteroarenes. The present protocol could be applied not only to trihalomethylative lactonization reactions involving trifluoromethyl, trichloromethyl, and tribromomethyl radicals but also to the first example of an organophotoredox-catalyzed imidative lactonization reaction involving a nitrogen-centered electrophilic radical species.