gem-Difluoro-cyclohexene and -cycloheptene derivatives through cyclization of gem-difluoroallyl radicals

6-Alkoxy-7-chloro-7,7-difluoro-5- [ (S)-(4-methylphenyl)sulfinyl]-I $heptadieneshave been transformed, through chlorine atom abstraction by tributyltin radical, into the corresponding difluoroallyl radicals, which, via intramolecular trapping by the vinyl group and reduction of the cyclohexenylmethyl and cycloheptenyl radicals obtained, gave gem-difluoro-cyclohexene and -cycloheptene derivatives. Reduction of the intermediate difluoroallyl radical afforded the corresponding dechlorinated open-chain difluoro compounds as side-products.