Asymmetric synthesis of (+)- and (-)- 2-(2-methoxyphenyl)-3,1-benzoxathiane

Enantiomerically pure (-)-(1R)-tricarbonyl-(2-methoxybenzaldehyde)chromium reacts with 2-mercaptobenzylalcohol to give the corresponding diastereomeric thioacetal complexes, which are separated and transformed quantitatively into the enantiomerically pure thioacetals (+)- and (-)-5 by removing the chromium tricarbonyl moiety. Copyright (C) 1996 Published by Elsevier Science Ltd