Free radical syntheses of new organofluorine systems

Abstract

Use of the carbon hydrogen bond as a functional group in free radical addition reactions to fluoro - alkenes has been studied. Reactions involving additions of cyclic alcohols and cyclic as well as acyclic diols to hexafluoropropene, yielded selective hydroxyl group directed products in high yield. The subsequent alcohol or diol - hexafluoropropyl adducts were easily dehydrated using thionyl chloride and pyridine, forming alkenes and dienes containing a polyfluoroalkyl moety, in good yield. The resultant alkenes following bromination and epoxidation, were found to be electrophilic in nature. Furthermore, these alkenes were dehydrogenated using sulphur, yielding aromatic compounds containing the hexafluoropropyl moiety, in high yield. Additions of hydrocarbons to hexafluoropropene gave complex final mixtures, illustrating the poor selectivity of such reactions.