Efficient and rapid regioselective deprotection of isopropylidene ketals

Abstract

A simple and efficient protocol is described for the regioselective hydrolysis of terminal isopropylidene ketal protection in carbohydrate derivatives 1a-11a. It uses either CoCl2·2H2O in acetonitrile or InCl3 in methanol at temperatures ranging from 50 to 60°C. The low cost of CoCl2·2H2O along with its requirement in catalytic quantities offers a great advantage for the multi-gram scale reaction. © 2005 Verlag der Zeitschrift für Naturforschung.