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The reactions of perfluoro-3-isothiocyanato-2-methyl-2-pentene with PPh3 and P(NEt2)3 in the presence of NaBF4, KI, and NaBPh4 form phosphonium salts with the heterocyclic substituent (4E)-5,5-bis(trifluoromethyl)-4-(tetrafluoroethylidene)-4,5-dihydro-1,3-thiazol-2-yl, instead of involving desulfurization and formation of P-F-containing products. The reaction with tris(pentafluorophenyl)phosphine fails. The reactions with P(OEt)3 in the presence of ClSiMe3 or (CH3O)2POSiMe3 yield diethyl or dimethyl [(4E)-5,5-bis(trifluoromethyl)-4-(tetrafluoroethylidene)-4,5-dihydro-1,3-thiazol-2-yl]phosphonates and no intramolecular alkylation products. The 1H, 13C, 19F, and 31P spectra are presented, and the reaction pathways are discussed. Potential mechanisms of the biological and catalytic activity of the reaction products are considered.

Reactions of 2-(imidazol-1-yl)-perfluoro-5,5-dimethyl-4-ethylidene-2-thiazoline with a series of secondary amines in THF resulted in the replacement of the imidazole moiety by the amine moiety.

The reaction of benzimidazoline-2-thione with perfluoro-2-methylpent-2-ene in the presence of triethylamine afforded (2E)-2-(tetrafluoroethylidene)-3,3-bis(trifluoromethyl)-2,3-dihydrothiazolo[3,2-a]benzimidazole whose structure was confirmed by X-ray diffraction analysis. The reaction pathways are discussed.

Perfluoro-2-methylpent-2-ene reacts with pyrazole, imidazole, 1,2,4-triazole, and benzotriazole to give products of the replacement of the vinylic fluorine atom. In the case of imidazole, the product of allylic fluorine substitution, 1,3-bisimidazolylperfluoro-2-methylpent-2-ene, is also formed. The structures of the products were confirmed by spectral data.