Zirconium tetrachloride (ZrC4) as an efficient and chemoselective catalyst for conversion of carbonyl compounds to 1,3-oxathiolanes

Different types of aldehydes and ketones can be efficiently converted into their corresponding 1,3-oxathiolanes using 2-mercaptoethanol (1.5-3.2 equiv.) in the presence of catalytic amount (0.04-0.15 equiv.) of ZrCl4 in CH2Cl2 as solvent at room temperature. Chemoselective monothioacetalization of aldehydes in the presence of ketones can also be achieved in high yield. The work-up is easy and removal of water is not necessary.