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 ...