Title of Thesis
Ligand 1,2 Diimidazlo Ethane & Its Binding Effect
on the Coordination Properties and Activity of Metals
Department of Chemistry / University of
|Number of Pages|
|Keywords (Extracted from title, table of contents and
abstract of thesis)|
Ligand, Diimidazlo Ethane, Binding Effect, Coordination, Properties, Activity, Metals, Thermogravimetric
1. Metal chelation is involved in many chemical, industrial and biological systems. The ligands 1,2- Diimidazoloethane (DIE) and 1,3-Diimidazolopropane (DIP), which can be viewed as N,N-substituted ethylenediamine and propylenediamine
respectively, form tetrahedral metal complexes of the type [M(L)X] where M=Zn (II) , Cd (I I) , Hg (I I) Cu(II) and CC) (II) and X= Cl Br', I', NO,' and L DIE and DIP. The stearic requirements of the two ligands are similar. The physical measurements of all the complexes indicate that DIE and DIP act as bidentate ligands.
2. The chelation behaviour of these ligands in solution were studied and followed by the synthesis of their metal derivatives, which were characterized by the elemental analysis and infrared spectra. The metal contents in these complexes was assayed by atomic absorption technique and electron microprobe. The purity of these new compounds were further ascertained through melting point.
3. The solid state infrared spectra of these complexes generally support tetrahedral geometry (MN2X2) with coordination
through pyrrole nitrogen atom. The effects of chelation on some characteristic bands were discussed and the solid state data are examined in the light of electronic spectra and conductance data of complexes in solution. The spectroscopic! and magnetic properties of these complexes were studied and compared.
4. Thermogravimetric analysis and differential thermal analysis have been employed simultaneously to investigate thermal stability, stoichiometry and mechanism of thermal decomposition of these complexes. The results provide information about complex fragmentation and transformation alongwith exothermic and endothermic changes.
The similarities in thermal stabilities of DIE and DIP complexes indicate similar geometric coordination.
5. New quantitative procedures for the estimation of
Bi(III), Hg(II) and Sb(III) based on their precipitation with DIE and DIP are reported.
6. In order to understand the comp-lexation behaviour of
1,2-Diimidazoloethane and 1,3-Diimidazolopropane with different
transition metal cations e.g., Cu++, Zn++, Cd++, Hg++, Co++ and Ni++, their stoichiometric studies were carried out at different pH values using Job's method of continuous variation. The stability constants of these metal derivatives were also calculated by the same method.
7. The antibacterial and antifungal activity of these chelates were tested against strain of bacteria: Staphylococcus aureus and Aspergillus niger by cylinder plate diffusion method.