Metal‐ and Photocatalyst‐Free Aerobic Photoinduced Benzyl C(sp3)−H Bonds Oxidation

Abstract

AbstractPhotoinduced the direct oxidation of benzyl C(sp3)−H bonds provides an attractive strategy for producing high‐value chemicals or intermediates. Unlike the conventional approaches that typically require transition‐metal catalysts, semiconductors, and organic photosensitizers as the photocatalysts, herein we report a bromine salt‐promoted photoinduced aerobic oxidation protocol for methylarenes. By applying NH4Br as both the bromine radical source and hydrogen atom transfer agent, photoinduced oxidation of methylarenes to the corresponding carboxylic products exhibits high conversion and selectivity. Furthermore, control experiments confirm that reactive oxygen species are proved to be essential for the success of this transformation. This strategy provides a metal‐/strong oxidant‐/photocatalyst‐free paradigm for the direct deep oxidation of methylarenes.