Reactions of α-Oxo Ketene Dithioacetals with Dimethylsulfonium Methylide: A New Versatile Synthesis of Furans and Butenolides

Article abstract of DOI:10.1021/jo00194a028

The reaction of 1-mono- and 1,2-disubstituted 3,3-bis(methylthio)-2-propen-1-ones 1 with dimethylsulfonium methylide (2) affords 2,2-bis(methylthio)-2,5-dihydrofurans 3 via epoxide 8 which can be isolated in a special case.A couple of methods including acid treatment effected the conversion of 3 to 2-(methylthio)furans 4, which are found to be useful synthons of a variety of furans and butenolides.Two naturally occurring furans, perillene and rosefuran, were synthesized by this method.