Skeletal Editing of Alkenes with Nitroarenes via Photoinduced Rearrangement of N─O═C Dipoles Forms Lactams and Amides

Photoinduced oxidative cleavage of alkenes with nitroarenes has proven to be an efficient approach for generating N─O = C dipoles. These dipoles exhibit diverse reactivity profiles, making the rearrangement of N─O═C dipoles a promising strategy for achieving nitrogen atom insertion in skeletal editing. Herein, we present a novel protocol for the synthesis of diverse lactam and amide derivatives through skeletal editing of alkenes using nitroarenes as nitrogen atom insertion reagents under light irradiation, offering the advantages of operational simplicity, high efficiency, and sustainability. Mechanistic studies and DFT calculations indicate that it proceeds through an intramolecular synergistic cyclization-cleavage-rearrangement process involving N─O═C dipoles, which realizes the cascade cleavage of C(sp²)═C(sp²) and C(sp³)─C(sp³) bonds and the insertion of the nitrogen atom, differing from previous understanding. This exploration highlights an emerging frontier in the application of N─O═C dipoles, offering potential for the development of novel skeletal editing strategies.