Visible-Light-Driven Nitrogen Radical-Catalyzed 3 + 2 Cyclization of Vinylcyclopropanes and N-Tosyl Vinylaziridines with Alkenes

A visible light photoredox-promoted and nitrogen radical catalyzed 3 + 2 cyclization of vinylcyclopropanes and N-tosyl vinylaziridines with alkenes is developed. Key to the success of this process is the use of the readily tunable hydrazone as a nitrogen radical catalyst. Preliminary mechanism studies suggest that the photogenerated nitrogen radical undergoes reversible radical addition to the vinylcyclopropanes and N-tosyl vinylaziridines to enable their ring-opening C-C and C-N bond cleavage and ensuing cyclization with alkenes.