Aerobic oxidation at benzylic positions catalyzed by a simple Pd(OAc)2/bis-triazole system

Abstract

An efficient catalyst system for the Pd-catalyzed aerobic oxidation of benzylic positions has been developed. The combination of palladium(II) acetate and 3,5-bis((1H-1,2,4-triazol-1-yl)methyl)benzoate ligand allows the selective oxidation at carbon adjacent to arene rings (primary and secondary benzylic alcohols, and other benzyl compounds) to provide the corresponding carbonyl and carboxy derivatives, employing molecular oxygen as oxidizing agent and a very low metal loading (10⁻⁵ mol%).