Visible‐Light‐Initiated Air‐Oxygenation of Alkylarenes to Carbonyls Mediated by Carbon Tetrabromide in Water

Abstract

AbstractSynthesizing benzyl skeleton derivatives via direct oxidation of functionalized benzylic C−H bonds has received extensive research attention. Herein, a method was developed to prepare carbonyl compounds via photoinduced aerobic oxidation of ubiquitous benzylic C−H bonds mediated by bromine radicals and tribromomethane radicals. This method employed commercially available CBr4 as a hydrogen atom transfer reagent precursor, air as an oxidant, water as a reaction solvent, and tetrabutylammonium perchlorate (TBAPC) as an additive under mild conditions. A series of substrates bearing different functional groups was converted to aromatic carbonyls in moderate to good yields. Moreover, a low environmental factor (E‐factor value=0.45) showed that the proposed method is ecofriendly and environmentally sustainable.