Base catalyzed [2,3]-sigmatropic rearrangements of propargylic sulfonium and selenonium salts

The synthesis and reactivity of bis-γ-substituted and unsubstituted propargylic sulfonium and selenonium salts under various basic conditions have been investigated. While the former compounds reacted only by [2,3]-sigmatropic rearrangement of the corresponding sulfur ylides, the latter salts exhibited a wider range of reactivity and showed potent DNA-cleaving properties.