Polyfluorophenyl acetylenes and related compounds

From the reaction of pentafluoro- and 4-substituted-tetrafluoroiodobenzene (the substituent group R being CF₃-, H-, CH₃- or CH₃O-) with copper(I) 3-(2′-tetrahydropyranyloxy)prop-1-ynide has been obtained the corresponding 3-(polyfluorophenyl) prop-2-ynol derivative. Where R = N(CH₃)₂- and NH₂- the acetylenic alcohol was not obtained; these were synthesized by the reaction of dimethylamine and ammonia with 3-(pentafluorophenyl)prop2-ynol itself. The acetylenic alcohols were converted to the corresponding polyfluorophenyl acetylenes by nickel peroxide in dioxan/aqueous NaOH. With benzene at 60° as solvent 3-(pentafluorophenyl)prop-2-ynol was oxidized to the aldehyde and acid and in refluxing benzene, 1-4bis(polyfluorophenyl)butadiynes and polyfluorophenyl acetylenes were obtained. The mechanism of some of the reactions has been discussed.