PHYSICO-CHEMICAL STUDIES ON THE COMPLEXES OF TRANSITION METALS WITH SOME SULPHUR BEARING LIGANDS

Abstract

A perusal of the literature on sulphur bearing ligands shows that considerable interest has been aroused by the complexes of 1,1 and 1,2-dithiolates with transition metals. The investigations on these complexes have covered a wide spectrum which includes general considerations of metal-sulphur bonding, electron delocalisation, potential biological activity and agricultural and technological applications. However, these studies have been mainly limited to their simple metal complexes with little attention having been paid to their mixed ligand complexes. This is inspite of the fact that introduction of another ligand normally increases the biological activity (especially fungicidal and insecticidal) to a considerable extent and modifies their properties so as to render them more useful for technical purposes. An attempt has, therefore, been made to prepare and characterise some mixed ligand complexes of potassium ethylxanthate, sodium diethyldithiocarbamate and 1jl-dithiolates derived from acetylacetone and malonicester with manganese, cobalt, nickel, copper, zinc and cadmium using 1,10-phenanthroline and 2,2,-bipyridyl as the second ligand. Further, it may be noted that metal complexes containing more than one metallic centre may show interesting catalytic and solid state properties provided there is provision for communication (of electrons) between the adjacent metal ions. The thiolates, by virtue of their 'A frame' structure in .......................