Solvent‐Free Catalytic Friedel–Crafts Acylation of Aromatic Compounds with Carboxylic Acids by Using a Novel Heterogeneous Catalyst System: p‐Toluenesulfonic Acid/Graphite

TsOH/graphite was found to be an effective catalyst system for the Friedel–Crafts acylation of aromatic compounds with carboxylic acids. Both aliphatic and aromatic carboxylic acids reacted smoothly under TsOH/graphite catalysis to afford the corresponding aromatic ketones in high yields. The graphite was easily recovered by simple extraction and could be reused without decrease of activity in the presence of fresh TsOH.