| abstract |
1,1,1,2,2-Pentafluoro-3,3-dichloropropane and 1,1,2,2,3-pentafluoro-1,3-dichloropropane are effectively prepared by reacting tetrafluoroethylene with fluorodichloromethane in the presence of a catalyst selected from the group consisting of an aluminum chlorofluoride of the formula: nAlCl x F y O z nwherein x, y and z are numbers which satisfy the equations: nx + y + 2z = 3, 0 < x < 3, 0 ≦ y < 3 and 0 < z < 3/2 nand anhydrous aluminum chloride provided that when the catalyst is anhydrous aluminum chloride, at least 2 moles of tetrafluoroethylene is reacted with one mole of fluorodichloromethane at a temperature of -20°C to +100°C. |