The reaction of Garner's aldehyde with dithioacetate enethiolates foll
owed by alkylation of the intermediate aldolate gives hydroxy-ketenedi
thioacetals with a moderate anti selectivity. This methodology was app
lied to the synthesis of various other ketene dithioacetals with high
E or Z stereoselectivity. (C) 1998 Elsevier Science Ltd. All rights re
served.