Heat-Induced Reactions of 6-Bromo-, 6-Chloro-, and 6-(Methylsulfanyl)octafl uoroindane-5-thiols with Tetrafluoroethylene. Synthesis of Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene

Abstract
Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene has been synthesized as the major product of co-pyrolysis of 6-bromo-, 6-chlorooctafluoroindane-5-thiols, or bis(6-bromo-5-perfluoroindanyl)disulfane with tetrafluoroethylene under flow conditions at 400-625ºC, along with small amount of tetradecafluoro-1,2,3,5,6,7-hexahydro-s-indacene. Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene formed in the reaction of 6-(meth-ylsulfanyl)octafluoroindane-5-thiol with tetrafluoroethylene at 420ºC has been isolated, and its structure has been confirmed by X-ray diffraction analysis. The schemes of the products formation involving intermediate radicals have been proposed.