POLYFLUORO-COMPOUNDS BASED ON THE CYCLOHEPTANE RING SYSTEM. PART 2. THE 1H,3H- and 1H,4H-DODECAFLUOROCYCLOHEPTANES, DERIVED UNDECAFLUOROCYCLOHEPTENES AND DECAFLUOROCYCLOHEPTA-1,4- and 1,3-DIENE

Article abstract of DOI:10.1016/S0022-1139(00)81487-6

From the mixture obtained by reaction of cycloheptane with cobalt(III) fluoride at 180-190 deg C, the cis- and trans-1H,3H- and 1H,4H-dodecafluorocycloheptanes were isolated.Each 1H,3H-compound was dehydrofluorinated by aqueous potash to 3H- and 4H-undecafluorocyclohept-1-ene, and thence decafluorocyclohepta-1,4- and 1,3-diene.The 1H,4H-isomers each gave 4H- and 5H-undecafluorocyclohept-1-ene and thence the two dienes on dehydrofluorination.The dichloro-adduct of the 5H-ene was reduced by lithium aluminium hydride, and the three possible 1H,2H,5H-undecafluorocycloheptanes were isolated.Likewise, the 4H-ene gave the 4 possible 1H,2H,4H-undecafluorides.All were identified by further fluorination with cobalt(III) fluoride at 160 deg C, to appropriate dodecafluorocycloheptanes.