Alkylation and aminomethylation of 1,3-dihydro-2tf-benzimidazole-2-thione

Alkylation of 1,3-dihydro-2H-benzimidazole-2-thione (2-mercaptobenzimidazole) with bromoethane and chloroacetic acid derivatives occurrs at the sulfur atom, leading to the corresponding 2-sulfanylbenzimidazole derivatives. Aminomethylation of 1,3-dihydro-2H-benzimidazole-2-thione with piperidine and 4-methylpiperidine gives reaction products at both nitrogen atoms, while reaction with morpholine gives derivative at only one nitrogen atom, which is in an equilibrium with the starting compound and bisadduct in DMSO solution. Keywords: 1,3-dihydro-2H-benzimidazole-2-thione, 2-mercaptobenzimidazole, 2-sulfanylbenzimidazole, alkylation, aminomethylation.