Benzoylation of benzene and substituted benzenes catalyzed by superacid ZrO₂:H₂SO₄

Superacid ZrO 2 :H 2 SO 4 showed high activity in Friedel—Crafts benzoylation of benzene and substituted benzenes such as chlorobenzene, toluene and 1,3,5‐trimethylbenzene. Benzophenones in 90–100% yields were obtained with catalytic amount of superacid ZrO 2 :H 2 SO 4 . The calcination temperature greatly influenced the acid strength and activity of the superacid ZrO 2 :H 2 SO 4 . The superacid has both Lewis and Bronsted acid sites. The reversibility of Friedel—Crafts benzoylation and transacylation were observed over the superacid. The used superacid could be readily regenerated and showed identical benzoylation activity to toluene.