Cross-linked polystyrene supported aluminium triflate (Ps-Al (OTf) 3) was found to be an efficient and chemoselective heterogeneous Lewis acid catalyst for the direct conversion of arenes to sulfones using sulfonic acids as sulfonylating agents. The solid acid catalyst is stable (as a bench top catalyst) and can be easily recovered and reused without appreciable change in its efficiency. Key Words: Sulfonylation, Sulfones, Sulfonic acids, Aluminium ...