Polystyrene and silica gel supported AlCl3 as highly chemoselective heterogeneous Lewis acid catalysts for Friedel–Crafts sulfonylation of aromatic compounds

Crosslinked polystyrene supported AlCl3 (Ps–AlCl3) and silica gel supported AlCl3 (SiO2–AlCl3) have shown to be mild and chemoselective heterogeneous Lewis acid catalysts for the sulfonylation of different kinds of aromatic compounds with p-toluene sulfonyl chloride (TsCl) and benzene sulfonyl chloride (PhSO2Cl) as sulfonylating agents. These solid acid catalysts are stable (as bench top catalysts) and can be easily recovered and reused without appreciable change in their efficiency.