Preparation method of 1, 1, 1, 4, 4, 4-hexafluorobutane

The invention discloses a preparation method of 1, 1, 1, 4, 4, 4-hexafluorobutane, and belongs to the technical field of fluorine-containing fine chemicals. According to the preparation method of 1, 1, 1, 4, 4, 4-hexafluorobutane, 3-chloro-1, 1, 1-trifluoropropane is used as a substrate, and under the conditions of cuprous halide and tert-butyl alcohol alkali metal salt, 3-chloro-1, 1, 1-trifluoropropane reacts with trifluoromethane in a reaction solvent to generate 1, 1, 1, 4, 4, 4-hexafluorobutane. The used 3-chloro-1, 1, 1-trifluoropropane is a byproduct generated in industrial production of 3, 3, 3-trifluoropropene, and the raw materials are wide in source, low in price and easy to obtain. The 1, 1, 1, 4, 4, 4-hexafluorobutane is prepared by a one-step method in the presence of cuprous halide and tert-butyl alcohol alkali metal salt, the raw material conversion rate is high, the product selectivity is high, and the yield is higher than 83%. The reaction process is short and controllable, the reaction cond