Sulfide fluonnation with

When there is an o.-hydrogen in the sulfide, the sulfuranes are unstable and cannot be isolated [775]. Sulfoxides [116] and sulfinylfluorides [117] are oxidatively fluonnated with fluorine to give hexavalent sulfur compounds in yields up to 90%. 

The KF-S reaction presumably involves attack of a fluonnated caibanion on sulfur, whereas the S-Sbp5 reaction may involve electrophilic attack by a cationic sulfur species on the olefin under the strong Lewis acid conditions Electrophilic attack on a fluonnated olefin may also account for formation of a perfluorinated sulfide from reaction of bis(pentafluorophenyl)disulfide with hexafluoropropylene under superacid conditions [IS5] (equation 28)... 

Condensation of thiophenoxide anions with various fluonnated polychloro- or polybromoethanes gives fluoroalkyl phenyl sulfides [57, 52, 55], These formal substitutions involve fluonnated olefins as intermediates [52, 55], In the case of perhalogenated ethanes, the mechanism shows a similarity with that of dihalo-genodifluoroinethane [52] (equations 46 and 47)... 

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