METHOD OF SYNTHESIS OF PERHALOGENATED CYCLOPENTENE Russian patent published in 2003 - IPC

FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to method of synthesis of chlorofluoro-cyclopentenes and octafluorocyclopentene used as intermediate compounds for synthesis of 1,2,3,3,4,4,5,5-octafluorocyclopentane. Method of synthesis of 1,2-dichloro-3,3,4,4,5,5-hexafluorocyclopentane is carried out by fluorination of octachlorocyclopentene with hydrogen fluoride in gaseous phase in the presence of the fluorination catalyst. Catalyst comprises compound taken among group consisting of . The fluorination catalyst is placed on a carrier. Activated carbon, aluminium oxide, partially fluorinated aluminium oxide, fluorinated aluminium are used as a carrier. Reaction temperature is from 150 to 800 C, contact time of hydrogen fluoride and octachlorocyclopentane is from 0.1 to 300 s, reaction pressure is from 1 to 10 kg/cm². The reaction product synthesized at stage of fluorination of octafluorocyclopentene with hydrogen fluoride is fluorinated with metal fluoride replacing chlorine atom in product for fluorine atom and octafluorocyclopentene is prepared. Metal fluoride is taken among the group involving: lithium fluoride, sodium fluoride, potassium fluoride, cesium fluoride and rubidium fluoride. EFFECT: improved technological parameters of process. 11 cl, 5 tbl, 28 ex