Preparation, fluorination and synthetic utility of a CFC-olefin adduct

Article abstract of DOI:10.1016/0022-1139(95)03326-2

1,1,1-Trichlorotrifluoroethane was added to ethylene using the catalyst system Fe/triethylphosphite, which eliminated the need for a solvent and avoided the corrosion problems inherent in CuCl-catalyzed reactions. The adduct, CF₃CCl₂CH₂CH₂Cl, was fluorinated with HF over a chromium(III) oxide catalyst. A series of alternating dehydrochlorinations and HF additions to internal C=C double bonds was proposed and supported by thermodynamic calculations to explain the formation of CF₃CF₂CH=CH₂ as the principal fluorination product. An intermediate, CF₃CCl=CHCH₂Cl, formed cleanly by dehydrochlorination of the adduct in the absence of HF, was converted into 4,4,4-trifluorobutanol and other compounds of the type CF₃CCl=CHCH₂X (X =OAc, OH, Br, I, H).