Liquid phase Friedel–Crafts benzylation of aromatics on a polymer-supported 12-tungstophosphoric acid catalyst

12-Tungstophosphoric acid (TPA) impregnated on polyaniline, zirconia and silica were chosen for the Friedel–Crafts benzylation of aromatics with benzyl alcohol as benzylating agent. TPA supported on polyaniline (PANI) was found to be selective towards monobenzylation and no dibenzylation was observed. This increased catalytic activity and selectivity can be attributed to the dispersion of TPA in the polyaniline matrix. The TPA supported on polyaniline was characterized by XRD, FTIR, BET and elemental analysis. The catalyst was found to be reusable for five cycles without appreciable loss in activity.