Nitryl Radical-Triggered Semipinacol-Type Rearrangement, Lactonization, and Cycloetherification of Olefins

Abstract

We report the development of a practical photocatalytic strategy to access various nitro-containing cyclic compounds from olefins via semipinacol-type rearrangement, cycloetherification, and lactonization reactions, employing N-nitrosuccinimide as a bench-stable, non-metal-based nitrating reagent. Mechanistic insights suggest that this light-driven process occurs via NO2 radical pathway mediated by a photoredox catalyst, which triggers an N−N bond fragmentation. Subsequent Giese-type addition of nitryl radicals to activated olefins takes place, leading to the formation of nitro-containing β-functionalized ketones, lactones and cycloethers. The reaction proceeds under mild reaction conditions and tolerates a wide range of functional groups and structural variations.