Polystyrene-Supported,Al(OTf)3-Catalyzed Chemoselective Synthesis of Acylals from Aldehydes

Cross-linked polystyrene-supported aluminium triflate Ps-Al(OTf)₃] has been shown to be a mild, efficient, and chemoselective heterogeneous Lewis acid catalyst for acetylation of aldehydes with acetic anhydride. The catalyst can be recovered simply and reused efficiently at least five times without any noticeable loss of catalytic activity.