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2.3. The reactions of fluorine-containing C-nucleophilic
compounds with sulphur halogenderivatives . Derivatives of
quadrivalent and hexavalent sulphur, containing haloid atoms, exchange
halogen groups for
different functional ones when nucleophilic reagents are acting. As a
result of this the main task is the generation of fluorine-contraining
carbanions and their introduction into reactions with sulphur compounds. One of
the approaches which are based on one of available and produced compounds is
generation of carbanions out of perfluorolefines under the action of alkali
metals fluorides. Thus sulfuryl fluoride joins to fluoroolefines in
presence of alkali metals fluorides in polar aprotic solvent, producing
respective sulfofluorides or sulfones [59].
 The mechanism of these changes is in
initial addition of fluoride-ion with fluoroolefine and generation of carbanion, reacting with sulfuryl fluoride.
Similarly, perfluoro-isopropylsulfonyl fluoride with 72% yield was obtained
from hexafluoropropylene and sulfuryl fluoride at the presence of KF [60].
2.4. The application of trimethyl(trifluoromethyl)silane in the synthesis
of trifluoromethane-sulfo-acid
and its derivatives. The other method is using of synthones on the base of IV group elements. Thus
if interaction of trimethyl(trifluoromethyl)silane with SO2 during absence of
anionic initiators doesn't take place then in presence of fluoride-ion
sources (for example, tetrabutylammonium fluoride (TBAF)), the formation of
tetra(n-butyl)ammonium trifluoromethanesulphite [61] takes place. It was
found that Me3SiONa in tetrahydrofurane was able to employ
instead TBAF. The further oxidization of
this salt by 30% hydrogen peroxide results in formation of
trifluoromethanesulfonate or free trifluoromethanesulfo-acid. Me3SiONa is rather effective as initiator of this reaction. Though total yield
of trifluoromethanesulfo-acid is not high (up to 30 %). At the same time this
method can be competitive regarding electrochemical fluorination method.
 In the work [62] it was shown that reaction CF3SiMe3 with
 -SO3 in
freon
113 runs rather easy at temperature gradient from –196 to 25 îÑ with
formation of trimethylsilyl ester of trifluoromethanesulfo-acid.
It's natural that CF3SiMe3 at conditions of
nucleophilic catalysis by fluoride-ion react with sulfo-compounds containing
labile atom of halogen. Thus during reaction with SOF2
(mole ratio of reagents 1:1 and 1:2) CF3SOF and (CF3)2SO
was produced. Similarly this system reacts with SOCl and SO2Cl2
[63].
 Analogously to this method
trifluoroetylenesulfo-acid can be obtained [64].
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