Method for producing 1,2,3,4-tetrachlorohexafluorobutane and method for purifying 1,2,3,4-tetrachlorohexafluorobutane

Disclosed is a method for producing 1,2,3,4-tetrachlorohexafluorobutane, which is characterized in that 1,2,3,4-tetrachlorobutane is reacted with fluorine in the presence of a solvent containing hydrogen fluoride. The 1,2,3,4-tetrachlorobutane may be obtained by chlorination of 3,4-dichlorobutene-1. Also disclosed is a method for purifying the thus-obtained 1,2,3,4-tetrachlorohexafluorobutane. This method enables to commercially efficiently produce 1,2,3,4-tetrachlorohexafluorobutane, which is useful as a synthesis material for hexafluoro-1,3-butadiene that is used, for example, as an etchinggas for semiconductors, by using 1,2,3,4-tetrachlorobutane which has been conventionally discarded as a by-product of chloroprene.