Synthesis and photophysical properties of tetra- and pentaalkynylfluorobenzenes by Sonogashira reactions of novel iodofluorobenzenes

1,2-Difluoro-3,4,5,6-tetraiodobenzene, 1,3-difluoro-2,4,5,6-tetraiodobenzene, 1,4-difluoro-2,3,5,6-tetraiodobenzene and 1-fluoro-2,3,4,5,6-pentaiodobenzene were prepared by oxidative iodination of fluorinated benzenes. Sonogashira cross-coupling reactions of these fluorinated periodobenzenes afforded fluorescent penta- and tetraalkynylfluorobenzenes in high yields.