Chlorofluorinated chain

Phosphonic derivatives bearing chlorofluorinated chains e.. diethyl-1,1,2-trifluoro-2-chloroethylphosphonate have been prepared by radical telomeriz-ation of chlorotrifluoroethylene with dialkyl hydrogenphosphonates in the presence of peroxide inhibitors. The 0,0-diethylaryldifluoromethylphos-phonothioates (230) undergo the sodium iodide-assisted thiono-thiolo rearrangement and subsequent Pd-catalysed dealkylation of (231) provides several 1,1-difluoromethylenephosphonothioic acids (232) (Scheme 61). These compounds can act as small molecule inhibitors for the protein tyrosine phosphatase enzymes. 

In addition, the chlorofluorinated Cl(CFClCF2)n chain activates the CC13 end group. Thus, the telomers produced can be used as original telogens for various telomerisations of non fluorinated monomers leading e.g. to form diblock cotelomer 6 [220,221 ] ... 

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