RESEARCH ON IMIDAZOBENZIMIDAZOLE DERIVATIVES. 23. SYNTHESES BASED ON 2-(2-HYDROXYETHYLAMINO)BENZIMIDAZOLES

Article abstract of DOI:10.1007/BF00475473

The possibility of annelation of the imidazoline ring on the basis of 2(2-hydroxyethylamino)-benzimidazoles was studied.It was shown that the action of hydrobromic, sulfuric, nitrosylsulfuric, and polyphosphoric acids, acetic anhydride, and phosphorus oxychloride on them does not lead to 2,3-dihydroimidazo<1,2-a>-benzimidazoles.In the case of POCl3 the products were 2-(2-chloroethylamino)benzimidazoles, treatment of which with alcoholic alkali led primarily to nucleophilic substitution of the chlorine atom by a methoxy group.Three-ring imidazolines are formed in 12-15percent yields in this case.It was established that the reaction proceeds through the intermediate formation of aziridine derivatives.