Synthesis and photochromism of dimers of 4,5-diaryl-2-(2,5-dimethylthiophen-3-yl)imidazolyl

4,5-Diphenyl, 4,5-di(4-methylphenyl), 4,5-di(4-methoxyphenyl)-2-(2,5-dimethylthiophen-3-yl)imidazoles were synthesized. Oxidation of the obtained imidazoles with potassium ferricyanide in water-alcohol solution of alkali gave the corresponding dimers. The structures were characterized by IR, ¹H NMR, mass spectroscopy and elemental analysis. The dimers showed photochromism in solution on irradiation.