Studies in the imidazole series

A new synthesis of derivatives of thiazolo3,2-a]benzimidazoles based on 2-halogenobenzimidazoles has been performed. The reaction of 2-chlorobenzimidazole with -halogeno ketones and the subsequent heating of the resulting 1-acylmethyl-2-chlorobenzimidazoles with thiourea has given 1-acylmethyl-2-mercaptobenzimidazoles. The cyclization of the latter under the action of mineral acids or water-abstracting agents has given a series of 2-alkyl-, 2-aryl-, and 2-heteryl-substituted thiazolo3,2-a]benzimidazoles.For Communication XLIX, see 1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 827–831, June, 1970.