Syntheses and Physical Properties of Several Octiphenyls Containing Mixed Linkages

抄録

Eight new linear octiphenyls containing two or three kinds of linkage were synthesized by the Ullmann homo-coupling reaction of iodoquaterphenyl. Among them, five compounds were alternatively synthesized by the Kharash-type Grignard cross-coupling of biphenylylmagnesium bromide and diiodoquaterphenyl or of terphenylylmagnesium iodide and diiodoquaterphenyl in the presence of bis (acetylacetonato) nickel (II). Spectral studies proved that the octiphenyls thus prepared displayed highly characteristic infrared, ultraviolet, and nuclear magnetic resonance spectra. Empirical Huckel molecular orbital calculations of the longest wavelength absorption bands of the octiphenyls were also performed. The calculated and observed wavelengths were in rather good agreement, except for the cases of two compounds.