Reaction Studies on the Conversion of Aryl Methyl Halides to Aryl Carbonyl Compounds Using Ph4PBr/EDTA/CaF2 as a Catalytic Oxidation System

We have developed an efficient protocol for the selective oxidation of arylmethyl halides to aromatic carbonyl compounds. This transformation employs tetraphenylphosphonium bromide (Ph4PBr) as both an oxidant and phase-transfer catalyst (PTC), in combination with EDTA and CaF2 as cocatalysts. Under mild reaction conditions, the method enables highly selective conversion of C-X bonds (X = Cl, Br) to carbonyl (C = O) functionalities. A diverse range of aromatic carbonyl products—including aldehydes, ketones, α-diketones, α-keto esters, and anhydrides—were obtained in good to excellent yields (50~95%).