THE SYNTHESIS AND LIGAND PROPERTIES OF N,N'-POLYMETHYLENE-BRIDGED IMIDAZOLE-2-THIONES AND BENZIMIDAZOLE-2-THIONES

A series of N,N'-polymethylene-bridged imidazole- and benzimidazole- 2-thiones have been made with the bridge containing 1 to 6 methylenes, the former by alkylation of N-methyl-imidazole by alpha,omega-dibromoalkanes followed by thiation with sulphur and the latter from the previously described bridged benzimidazolones by treatment firstly with phosphoryl chloride followed by thiourea. The bridged benzimidazolethiones formed complexes with mercury, palladium and copper salts but not with iron, cobalt, nickel, zinc, platinum, cadmium, silver or thallium . The imidazolethiones complexed with iron. cobalt, nickel, copper, zinc, tin, cadmium. palladium, platinum and silver salts.