Photoexcited nitroarenes for the oxidative cleavage of alkenes

Abstract

The oxidative cleavage of alkenes is an integral process that converts feedstock materials into high-value synthetic intermediates^1-3. The most viable method to achieve this in one chemical step is with ozone^4-7; however, this poses technical and safety challenges owing to the explosive nature of ozonolysis products^8,9. Here we report an alternative approach to achieve oxidative cleavage of alkenes using nitroarenes and purple-light irradiation. We demonstrate that photoexcited nitroarenes are effective ozone surrogates that undergo facile radical [3+2] cycloaddition with alkenes. The resulting 'N-doped' ozonides are safe to handle and lead to the corresponding carbonyl products under mild hydrolytic conditions. These features enable the controlled cleavage of all types of alkenes in the presence of a broad array of commonly used organic functionalities. Furthermore, by harnessing electronic, steric and mediated polar effects, the structural and functional diversity of nitroarenes has provided a modular platform to obtain site selectivity in substrates containing more than one alkene.