abstract |
PURPOSE: To obtain the title compound through adding dichlorofluoromethane to tetrafluoroethylene in the presence of a Lewis acid catalyst by making the molar ratio for both the components equivalent or higher for the former to the latter to suppress disproportionation. n CONSTITUTION: When the objective compound is to be obtained by addition reaction of dichlorofluoromethane (R21) to tetrafluoroethylene (4F) in the presence of a Lewis acid catalyst, the amounts of 4F and R21 to be used should be e.g. ≥1 (pref. 1-3) in the molar ratio 4F/R21. The Lewis acid catalyst is a halide containing an element such as Al, Sb, Nb, Mo, Ga or Zr. The raw materials are continuously fed into a reactional vessel at the above molar ratio and the reaction product containing the objective compound is withdrawn in a continuous manner from the reactional vessel, thus suppressing the concentration of R21 to a minimum. Thereby, by-products due to the disproportionation of R21 will not be formed, leading to high yield of the objective compound. n COPYRIGHT: (C)1991,JPO&Japio |