Metal-Free Photooxidation of Toluene Derivatives into the Corresponding Carboxylic Acids and Aldehydes by a HBr/NaOCl·5H2O System

Abstract

Photobromination of toluene derivatives using blue LED (454 nm) or UV LEDs (365, 385, 395 nm) with aqueous HBr and NaOCl·5H₂O in trifluoromethyl benzene afforded the corresponding benzoic acids derivatives. The intermediates were (dibromomethyl)benzene derivatives, isolated in a nitrogen atmosphere. The dibromomethyl benzene derivatives afforded the corresponding aldehydes. After the reaction with HBr, the aqueous layer could be recovered and reused.