Thiosulfonium ions

Thiosulfonium ions where one of the alkyl groups is an allyl group can undergo a different sort of rearrangement (50), a [2,3] sigmatropic shift of the... 

The allyl thiosulfonium ions shown in (50) were generated by the reaction of R S—X (X = Cl or SMe2) with allylic sulfides RSCH2CH=CH2. It is interesting, although not surprising in view of the rapid rate of a process like... 

Given that the rate-determining step of the disulfide-sulfinic acid reaction is (117), and that sulfides are considerably more reactive than disulfides as nucleophiles in displacements on thiosulfonium ions (Smallcombe and Caserio,... 

Thiosulfonium ions derived from methylation of substituted 1,2-dithianes (94a) were found to exist in undistorted chair conformation with the methyl group in axial position.254 The phenomenon was interpreted to result from minimizing electron repulsion in orthogonal position (94b) (ab initio calculation at STO-3G //STO-3G level). Unlike 1,2-dithianes, methylation of 1,2-dithiolanes and substituted thianes to form the corresponding. S -methylsulfonium hexafluorophosphate and perchlorate salts255 is non-stereoselective. 

Ally lie sulfides react with DMTSF chemoselectively at the sulfur atom, generating thiosulfonium ions. This ion formation is reversible and the allylic thiosulfonium ion is capable of a [2,3]-sigmatropic rearrangement before subsequent electrophilic addition to the alkene. ... 

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