METHOD OF PRODUCING 5-TRIFLUOROMETHYL-3,6-DIOXA-8-SULPHONYLFLUORIDE PERFLUOROCTENE Russian patent published in 2024 - IPC C07C303/02 C07C309/82 

FIELD: chemistry.

SUBSTANCE: invention relates to chemical engineering and specifically to a method of producing 5-trifluoromethyl-3,6-dioxa-8-sulphonylfluoride perfluoroctene. Method involves reaction of 2,5-di(trifluoromethyl)-3,6-dioxa-8-sulphonylfluoride perfluorooctanoylfluoride with sodium carbonate in diglyme medium while heating, treatment of obtained solution of 2,5-di(trifluoromethyl)-3,6-dioxa-8-sulphonylfluoride perfluorooctanoate of sodium with alkali metal hydride and pyrolysis of treated 2,5-di(trifluoromethyl)-3,6-dioxa-8-sulphonylfluoride perfluorooctanoate of sodium in diglyme medium. Initial 2,5-di(trifluoromethyl)-3,6-dioxa-8-sulphonylfluoride perfluorooctanoyl fluoride is preliminarily passed through a column with anhydrous potassium fluoride, alkali metal hydride used is calcium hydride, and the pyrolysis process is carried out by feeding 2,5-di(trifluoromethyl)-3,6-dioxa-8-sulphonylfluoride perfluorooctanoate of sodium into boiling anhydrous diglyme with simultaneous separation of organofluorine layer at temperature from -10 °C to -20 °C on phase separator, where the first portion of the product containing the increased content of impurity 2-hydro-1,1,1,2,4,4,5,7,7,8,8-undecafluoro-5-trifluoromethyl-8-sulphonylfluoride-3,6-dioxaoctane, in amount of 1–3% is selected as solvent stripper, with subsequent extraction of target product.

EFFECT: method of producing 5-trifluoromethyl-3,6-dioxa-8-sulphonylfluoride perfluoroctene, characterized by a simpler and safer process with maintaining high output and high purity of the end product.

3 cl, 2 ex