Synthesis of low molecular weight perfluoro oxymethylene vinyl ethers

Perfluoro oxymethylene vinyl ethers have been formed by a multi-step synthesis. The key intermediates are low molecular weight perfluoropolyether (PFPE) fluoroformates CF₃O(CF₂O)_nCOF (I) n=1-6 obtained from the photo-oxidation of perfluoro propene (HFP) in perfluorohexane. Under certain conditions the light-mediated fluorination of PFPE fluoroformates (I) gives PFPE hypofluorites CF₃O(CF₂O)_nCF₂OF (II), which can be added to sym dichlorodifluoroethene to form the dichloro adduct CF₃O(CF₂O)_nCF₂OCFClCF₂Cl (III) which, after dechlorination, gives the desired vinyl ethers CF₃O(CF₂O)_nCF₂OCFCF₂ (IV). Every reaction step has to be properly controlled as far as the reaction variables are concerned. A mechanistic scheme is presented that is consistent with the observed experimental data.