Abstract

For each of the imidazole equilibrium tautomers mixtures, 2-phenyl-4(5)- and 2-ethyl-4(5)-methylimidazole, 2-phenyl-5- and 2-ethyl-5-imidazole isomers, respectively, were isolated, in a pure state by means of inclusion complexation with a host compound. In the case of 4(5)-methylimidazole, however, it was the pure 4-methylimidazole tautomer that was isolated as its inclusion complex with the rac-bis-β-naphthol host. In the latter case, it was found that (+)- and (−)-bis-β-naphthol molecules form a hydrogen bonded pair, and 4-methylimidazole binds to the host through OH⋯N and NH⋯O hydrogen bonds.