METHOD FOR PRODUCING 5-TRIFLUOROMETHYL-3,6-DIOXA-8-PERFLUOROCTENE SULPHONYL FLUORIDE Russian patent published in 2012 - IPC C07C309/82 C07C303/02 

FIELD: chemistry.

SUBSTANCE: invention refers to industrial chemistry, particularly a method for producing a fluorinated vinyl ether containing a sulphonyl fluoride group, namely 5- trifluoromethyl-3,6-dioxa-8-perfluoroctene sulphonyl fluoride which is applicable as a fluoride-containing monomer for producing fluoropolymers used as a base to make ion-exchanger membranes. The method for producing 5-trifluoromethyl-3,6-dioxa-8-perfluoroctene sulphonyl fluoride consists in conducting a reaction of 2,5-di(trifluoromethyl)-3,6-dioxa-8-perfluoroctanoyl fluoride sulphonyl fluoride and sodium carbonate in diglyme, separating diglyme at low pressure and conducting pyrolysis of the produced sodium salt of 2,5-di(trifluoromethyl)-3,6- dioxa -8-perfluoroctanic acid sulphonyl fluoride at high temperature with pyrolysis of the sodium salt of 2,5-di(trifluoromethyl)-3,6-dioxa-8-perfluoroctanic acid sulphonyl fluoride conducted at initial temperature 60°C increasing to 220-230°C at (35-40)°C/h at pressure drop from 300 to 30 mm Hg.

EFFECT: developing the method for producing the fluorinated monomer enabling creating its effective technology, and conducting pyrolysis in 'mild' conditions to decrease the yield of resinous by-products.

3 cl, 2 tbl, 11 ex