Stable fluoroaliphatic radicals containing functional groups: Synthesis and reactivity

Article abstract of DOI:10.1016/S0022-1139(96)03491-4

β-Fluorosulphatoperfluoroalkyl radicals (3, 7 and 8) are obtained by the reaction of fluoroolefins (HFP trimer and dimer, and perfluoro-4,4-dimethylpent-2-ene, respectively) with (FSO₃)₂. The pure β-fluorosulphatotetrafluoroethylperfluorodiisopropylmethyl radical (3) has been isolated and converted to the perfluoroacetyldiisopropylmethyl radical (4) under the action of CsF. The reaction of radicals 3, 7 and 8 with SbF₅ leads to the replacement of the FSO₃ group by a fluorine atom. The ability of the FSO₃ group in β-fluorosulphatoperfluoroalkyl radicals to play the role of a leaving group is explained by the stabilizing effect of the unshared electron on the adjacent carbocation centre.