SYNTHESIS AND CHARACTERIZATION OF SOME BIVALENTMETAL COMPLEXES OF BIOACTIVE LIGANDS HAVINGBENZIMIDAZOLEMOIETY

Abstract

Cadmium, Mercury, and lead are three of the most harmful metal contaminants to human health and well-being. Cd (II), Hg (II), and Pb II complexes of the type [M(L1-3)X2] have been produced with three of the ligands, namely 2,5-bis (2-thiomethylenyl- benzimidolozolyl) 1,3,4-thiadiazole and 2-(picolinyl)-2- (benzimidozolyl) ether. It is clear from the 2917 cm-1 medium band in the free ligands due to (NH) vibration that these ligands remain in Keto form when solidified. There is no enolisation or deprotonation of ligands in complexes and they remain neutrally attached to the bivalent metal ions. It appears that picolinic N, etherial O/S, and azomethenic nitrogen in complexes can be coordinated by newly discovered bands in the far infrared range. At 1535-1540 and 1365-1370 cm-1, two lines in the Pb (II) spectra support the coordination of the acetate group to the Pb (II) ion through one octahedral oxygen, which indicates the monodentate acetate group's coordination to Pb