الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
The present thesis entitled; (Synthesis and characterization of some metal complexes derived from Schiff bases and azo compounds of 4,4`-methylenedianiline: Evaluation of their biological activities on some land snails species) comprises of three chapters. The first chapter is concerned with the literature survey of azo, Schiff base compounds and their metal complexes especially those of biological activity and structural viewpoints. The second chapter is related to the experimental part of the azo ligand; bis-(1,5-dimethyl-4-[(E)-(3-methylphenyl)diazenyl]-2-phenyl-1,2-dihydro-3-H-pyrazol-3-one) (L1) and the Schiff base ligand; (bis-((E)-2-(4-ethylphenyl-imino)-1,2-diphenylethanone) (L2). The ligands and their Co(II), Ni(II), Cu(II), Pd(II), Zn(II), Cd(II), Pb(II) and Sn(IV) complexes were prepared and their structures were investigated by elemental analyses, magnetic susceptibility, molar conductivity, spectral studies (IR, UV–Vis, 1H NMR and ESR) and thermogravimetric analyses. The third chapter is divided into two parts:- • The first part involves the discussion of the results concerned with the azo ligand and its metal complexes. The octahedral metal complexes (1, 2, 3, 9) are formed with molar ratio (1M:2L) and chemical formulae; [M(L1)2Cl2].mEtOH.nH2O, (where; m= (7.25, 5.25, 2.75) and n= (0, 0, 1.5)) for complexes (1, 2, 3), respectively, and [Pb(L1)2(CH3COO)2].6.5EtOH complex (9). Also, the sandwich octahedral Cu(II) complexes (4, 5, 6) separated from the reactions of the azo ligand with Cu(II) chloride (in presence of ammonia solution), acetate and perchlorate salts have chemical formulae; [Cu2(L1)2Cl4].3EtOH.3H2O, [Cu2(L1)2(CH3COO)2(OH)2].4.5EtOH.0.5H2O and [Cu2(L1)2(ClO4)4].9.5EtOH, respectively. Moreover, the square planar [Pd(L1)Cl2].1.5EtOH.1.5H2O (7) and the octahedral [Sn(L1)Cl4].5.75EtOH (8) are formed. The molar conductivity values reveal that the anions are directly attached to the metal ions. The ESR spectra of the solid Cu(II) complexes showed an axial symmetry with 2B1g as a ground state with hyperfine structure. The mode of interaction between the azo ligand and different metal ions was achieved from the infrared spectra which suggest that the ligand reacts with metal ions via its half unit (ON). i.e. as a bidentate not a tetradentate ligand. The thermal decomposition behavior of the ligand and its metal complexes was discussed based on thermogravimetric analyses. The follow-up of the pathway of the thermal decomposition and final residues confirmed the chemical formula and geometrical structure of the prepared metal complexes. The thermal decomposition reactions ended with the formation of metal or metal oxide contaminated with carbon. The activation thermodynamic parameters, such as activation energy (E*), enthalpy of activation (ΔH*), entropy of activation (ΔS*) and Gibbs free energy (ΔG*) have been calculated using DTG curves. • The second part includes the characterization of the Schiff base metal complexes which were prepared by direct and template reaction methods. Analytical and spectral studies establish that the direct reaction method gave tetrahedral trinuclear complexes; [Co3(L2)Cl6].0.5EtOH.7.5H2O complex (1), [Ni3(L2)Cl6].12.25H2O complex (2) and square planar trinuclear [Cu3(L2)Cl6].6H2O complex (3). However, the template reaction method produced octahedral complexes (4-8) with different stoichiometry; (3M:1L), (2M:1L) and (1M:1L). The formed complexes (4, 5) have chemical formulae; [Co3(L2)Cl5(H2O)7].Cl.4.5EtOH and [Ni2(L2)Cl4(H2O)4].2EtOH, respectively. While, the sandwich Cu(II), Zn(II) and Cd(II) complexes (6-8) are separated with chemical formula; [M2(L2)2Cl4].m.EtOH.nH2O, where; m= (0.25, 0, 0.25) and n= (13, 13.5, 10.5), respectively. The molar conductivity values revealed that all complexes (except 4) are non- English Summary IX electrolytes, whereas, the molar conductivity value of Co(II) complex (4), typified 1:1 electrolyte. The important infrared spectral bands of the ligand and its solid metal complexes imply that the ligand coordinated to the metal ions in a neutral tetradentate manner via the azomethine nitrogen and carbonyl oxygen atoms. The ESR spectra of solid copper(II) complexes in powder form showed an axial symmetry with (dx2-y2) as a ground state and high covalent character of metal-ligand bond with distorted symmetry. The thermal decomposition behavior pathways of the ligand and its metal complexes have been studied by (TG/DTG) analyses. The final thermal decomposition products are (metal oxide or metal oxide + C), this was confirmed with X-ray diffraction analysis (XRD) for the final product of the thermal decomposition of Co(II) complexes (1, 4) and Cu(II) complex (6). The thermal decomposition mechanism of metal complexes (1-3) concluded that the formation of metal oxide is attributed to oxygen atoms of the ligand as well as that of lattice water molecules. The thermodynamic and kinetic parameters of the thermal decomposition were evaluated and discussed. The change of entropy values (ΔS*) for the thermal decomposition steps showed that the transition states are more ordered, i.e. in a less random molecular configuration than the reacting complexes. Also, the fraction appeared in the calculated order of the thermal reactions (n), confirmed that the reactions proceeded in complicated mechanisms.