Research on aminomethylene derivatives of azoles. 23. Synthesis and structure of formyl derivatives of 1-phenyl-5-hydroxy(mercapto)-imidazoles

1-Phenyl-4-formyl-5-hydroxy(mercapto)imidazoles were obtained by replacement of the chlorine atom in 1-phenyl-4-formyl-5-chloroimidazole by hydroxy and mercapto groups, and their physicochemical properties and structures were studied. It was shown by a comparison of the electronic and IR spectra (and the PMR spectra in the case of the sulfur-containing compound) with the spectral characteristics of compounds that model the various possible tautomeric forms that 1-phenyl-4-formyl-5-hydroxy (mercapto)imidazoles exist primarily in the mesoionic form; this is associated with their high acidities and the presence of a sufficiently basic ring nitrogen atom.See 1] for Communication 22.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 670–674, May, 1979.