Iodine: A versatile reagent in carbohydrate chemistry IV. Per-O-Acetylation, regioselective acylation and acetolysis

Iodine has been found to be an effective Lewis acid for promoting the per-O-acetylation of unprotected sugars. Under controlled conditions it can bring about regioselective acylation of carbohydrate derivatives. At higher concentration and with longer reaction times, iodine can effect the selective acetolysis of benzyl ether-protected primary hydroxyl groups. All of these reactions proceed in high yield, are easy to carry out and make use of readily available iodine, which is both cheap and easy to handle.