Six Lewis acids have been investigated as possible catalysts for the acylation of ketones with anhydrides to give p-diketones. Of these reagents, only two, anhydrous ferric chloride and anhydrous zinc chloride, are satisfactory. In the attempted acylation of acetophenone with acetic anhydride in the presence of aluminum chloride, only dypnone was obtained; while the use of either iodine or anhydrous stannic chloride as the catalyst gave benzoic ...
