Phosphorylation of Benzimidazole-2-thiones by Chloroethynylphosphonate

Resumo

The reaction of chloroethynylphosphonates with N-substituted benzimidazole-2-thiones proceeded chemo- and regioselectively with the formation of cyclic zwitterions, namely alkyl (9H-benzo[4,5]imidazo[2,1-b]-thiazol-3-yl-4-ium)phosphonates. Chemo- and regioselective reaction of N-unsubstituted benzimidazole-2-thione with chloroethynylphosphonates led to the production of linear Z-1,2-bis(1H-benzimidazol-2-ylsulfanyl)-ethenylphosphonates.