Method for producing 1,1-dichloro-2,2,3,3,3-pentafluoropropane

1,1-dichloro-2,3,3,3 useful as starting substances to obtain a tetrafluoropropene (R1214ya) 1,1-dichloro-2,2,3,3,3-pentafluoropropane ( to provide a method for producing in HCFC-225ca) high content ratio. Consists of one or more of the mixture of isomers of dichloro-pentafluoropropane (HCFC-225), the HCFC-225ca content ratio is less than 60 mol% starting material for the presence of a Lewis acid catalyst or metal oxide catalyst the by isomerization reaction, the content ratio of HCFC-225ca in the product, characterized in that to increase than the content ratio in the feed.