PREPARATION OF 1-CHLORO-2-TRIFLUOROMETHYL-3,3,3- TRIFLUOROPROPENE FROM ISOBUTYLENE

PREPARATION OF 1-CHLORO-2-TRIFLUOROMETHYL- 3,3,3-TRIFLUOROPROPENE FROM ISOBUTYLENE Isobutylene is catalytically converted to 1-chloro-2-trifluoromethyl-3,3,3-trifluoropropene ¢(CF3)2C = CHCl! in a chlorofluorination reaction zone by passing a mixture of anhydrous hydrogen fluoride, chlorine and the isobutylene over a chromium oxide or metal fluoride chlorofluorination catalyst. Alternatively, the isobutylene feed is first prechlorinated, and the mixture of prechlorination fed for conversion to the desired (CF3)2C = CHCl, to a downstream fluorination reactor charged with the chlorofluorination catalyst. The 1-chloro-2-trifluoromethyl-3,3,3-trifluoropropene product is of value as an intermediate in the preparation of hexafluoroisobutylene.