Mediated Electrochemical Synthesis of Aromatic Aldehydes, Ketones, and Quinones Using Ceric Methanesulfonate

Article abstract of DOI:10.1021/jo00268a010

Cerium(IV) in aqueous methanesulfonic acid is an excellent reagent for the oxidation of alkyl aromatics and polycyclic aromatics to aldehydes, ketones, and quinones.The benefits of methanesulfonic acid include low cost, low nucleophilicity, stability to anodic and electrochemical oxidation, and high solubility of Ce(III) and Ce(IV) in aqueous solutions of this acid.The properties of this medium are ideal for electrochemical regeneration, giving current efficiences up to 89percent at 500 mA/Cm².With this system, enhanced yields of menadione were obtained by adding Cr(VI).A new solid oxidant, Ce(CH3SO3)2(OH)2*H2O, was produced electrochemically, providing a convenient starting material for these oxidations.Improved selectivity was obtained in the synthesis of m-phenoxybenzaldehyde by using this solid material in place of soluble Ce(IV).