Perfluoro(2-propoxypropionyl) fluoride (1a), which is the precursor of the
perfluorinated propyl vinyl ether (PPVE) monomer of an industrially importa
nt perfluoroalkoxy copolymer (PFA), was synthesized by utilizing direct flu
orination of the non-fluorinated counterpart for the first time. The partia
lly-fluorinated ester 7 synthesized from the desired perfluorinated acid fl
uoride la itself and tile non-fluorinated alcohol 5, which has a carbon ske
leton corresponding to the desired compound 1a, was perfluorinated by liqui
d-phase direct fluorination with elemental fluorine. Degradation of the res
ulting perfluorinated ester 8 gave 2 mols of the desired acid fluoride 1a.
In a sense, this process can be called self-multiplication of a perfluorina
ted acid fluoride from a non-fluorinated alcohol.