Adamantylation of Imidazoles and Benzimidazole

For the first time is reported on substitution of a hydrogen atom in position 4 of the imidazole ring with an aliphatic substituent occurring in reaction between 1-bromoadamantane and imidazoles. The reaction proceeds alongside the substitution in position 1 at heating in excess imidazole. In o-dichlorobenzene solution adamantylation of benzimidazole afforded 1-(1-adamantyl)benzimidazole and 1,3-di(1-adamantyl)benzimidazolium bromide. The specific features of the reactions course are described. The structure of compounds obtained is proved by ¹H NMR spectroscopy.