GaAlClx-grafted Mont.K-10 clay: Highly active and stable solid catalyst for the Friedel-Crafts type benzylation and acylation reactions

A liquid phase reaction of anhydrous GaCl3 and AlCl3 with the surface hydroxyl groups (with HCl evolution) of Mont.K-10 clay in dry CCL4 under reflux resulted in a novel GaAlClx-grafted Mont.K-10 catalyst [with Cl/(Ga + Al) = 1]. The catalyst showed high activity and stability in the Freidel-Crafts type benzylation and benzoylation (by benzyl chloride and benzoyl chloride, respectively) of benzene, naphthalene and substituted benzenes, even in the presence of moisture. It also showed good activity for the benzoylation of nitrobenzene (i.e. even in the presence of strong electron withdrawing group, like nitro group, attached to the benzene ring). The catalytically active surface species in the catalyst are –(O)2–Ga(or Al)Cl.