Regioselective side-chain as well as nuclear monobromination of aromatic substrates with N-bromosuccinimide using phosphotungstic acid supported on zirconia as a heterogeneous catalyst

Abstract Regioselective monobromination of aromatic substrates with N -bromosuccinimide has been achieved in excellent isolated yields (84–98%) using phosphotungstic acid supported on zirconia as a novel heterogeneous catalyst. The catalyst has been characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), surface area and acidity measurements. Remarkably, the new catalyst system described brought about the side-chain bromination of aromatics to afford bromomethyl arenes in excellent yields (86–98%) without the need for a radical initiator. Recovery and recylability of the catalyst have been well established.