A highly efficient and catalytic synthetic protocol for oxathioacetalization of carbonyl compounds

A variety of aldehydes and ketones can be converted easily to the corresponding 1,3-oxathiolane derivatives, on treating with 2-mercaptoethanol using a catalytic amount of bromodimethylsulfonium bromide as pre-catalyst at room temperature under solvent-free conditions. Some of the major privileges are: mild reaction conditions, high yields, no aqueous work-up and no chromatographic separation; which is highly economic and compatible in the presence of other protecting groups. Furthermore, no brominations occur either at the double bond or alpha to the keto position and even in the aromatic ring. (C) 2004 Elsevier B.V. All rights reserved.