Thermal reactions of hexafluorobutadiene and hexafluorocyclobutene with elemental sulphur

Article abstract of DOI:10.1016/S0022-1139(00)80855-6

Hexafluorobuta-1,3-diene and hexafluorocyclobutene interact with elemental sulphur under conditions of mutual conversion (>/= 280 deg C) to give the same products, hexafluoro-3,6-dihydro-1,2-dithiine (1), hexafluorothiolene-3 (2) and hexafluorothiolanethione (3).The product composition and ratio depend on the reaction conditions.Dithiine 1 and thiolene 2 were formed in competitive reactions.Their thermal stability and the retrocycloaddition reaction of dithiine 1 have been studied.The latter reaction results in thiolene 2 in addition to the formation of hexafluorocyclobutene.This is consistent with a stepwise mechanism for the retrocycloaddition as well as the cycloaddition reaction.