Absorption Spectrum of 2-[p-(4, 5-biphenyl-2-imidazolyl)phenyl]-4-ethoxy-4, 5-Biphenyl-4H-imidazole

Abstract

The longest wavelength electronic absorption bands (Table 1) of 2-aryl-4, 5-diphenylimidazoles show bathochromic shifts when more electron-attractive substituents are introduced in the 2-phenyl group. The substituept effect is closely related to that in the intramolecular charge-transfer bands of 1-(p-isubst4uted phenyl)pyrroles. Therefore, the longest wavelength absorption band of 2-[p- (4, 5-dipheny1-2-imidazolyl)phenyl]-4-ethoxyl-4, 5-dipheny1-4H-imidazole is considered as, mtramolecular charge-transfer band. The solvent and temperature effects are consistent. With this'interpretation.