Reactions of cyclic sulfur ylides with some carbonyl compounds

The reaction of a six-membered sulfonium Wide 5 with aldehydes or ketones afforded the oxirane derivatives 6a-d as a mixture of cis and trans isomers in excellent yields. In addition, the same reactions, using five- or six-membered cyclic oxosulfonium ylides 7 and 11, gave the corresponding oxirane derivatives in good yields. Moreover, the reaction of 11 with two equimolar amounts of base and 4-hexen-3-one afforded the cyclooctene oxide derivative 16 with high stereoselectivity in 59% yield via a sequential Michael-Michael-type addition of the ylide and the resulting enolate ion followed by an intramolecular Corey-Chaykovsky reaction. (C) 2002 Wiley Periodicals, Inc.