الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
• The first one deals with a general review on the coordination chemistry, biological activity of azo compounds mainly from the structural view point. The second chapter is concerned with the experimental work. Five azo ligands The third chapter includes the results and discussion and consists of four parts: • In the first part the results obtained from the potentiometric studies of [HL1- HL5] are given. The dissociation constant (Pk1H) was obtained by the titration 0.001 M ligand in 20% (v/v) DMF-water mixture with 0.02 M NaOH at different temperatures (298, 308 and 318 K) and ionic strength 0.1 M KCl. These values were confirmed by different computational methods. • In the second part the successive stability constants (log K1 and log K2) of the complexes of HL1- HL5 with Fe2+, Cd2+, Fe3+ , UO22+and Zr4+ were determined using different computional methods in 20% (v/v) DMF-water mixture at 298, 308 and 318 K. For all the complexes formed log K1 > log K2, because the vacant sites of the metal ions are more freely available for the tinding of a first ligand than for a second one. The order of stability constants are in agreement with that found by Irving and Williams for [HL1- HL5] polymeric complexes at 298 K. Zr4+> UO22+ > Fe3+ > Cd2+ > Fe2+ The dissociation constant (pk1H) of [HL1- HL5] decreases with increasing temperature revealing that the acidity of the ligands increases with increasing temperature. The dissociation processes are non-spontaneous, endothermic and entropically unfavourable. For [HL1- HL5] complexes the stepwise stability constants (log K1 and log K2) increases with increasing temperature in the case of Fe2+, Cd2+, Fe3+ , UO22+and Zr4+ ( i.e. favorable at higher temperature). The negative value of G for the complexation process of, Fe2+, Cd2+, Fe3+ , UO22+ and Zr4+ with [HL1- HL5] suggests a spontaneous nature of such process. For the complexation process of Fe2+, Cd2+, Fe3+ , UO22+and Zr4+ with [HL1- HL5] the H values are positive (endothermic process and favorable at higher temperature). The S has a positive value indicating that the formation of such complexes are favorable. • In the third part a series of Cu(II) polymer complexes with ligands (HL1-3) have been prepared and fully characterized. The coordination behaviour of the anions is also discussed on the basis of IR and molar conductance measurements. It was observed that coordination of anions with metal was effected by number of coordination sites, which was further confirmed by molar conductance. The geometries of the polymer complexes are also effected by number of coordination sites and ligand (HLn) has four coordination sites and formed different geometrical complexes with different anions. SO4 complexes of both • In The fourth part a series of Ni(II) polymer complexes with ligands (HL1-5) have been prepared and fully characterized. coordination behaviour of the anions is also discussed on the basis of IR and molar conductance measurements. It was observed that coordination of anions with metal was effected by number of coordination sites, which was further confirmed by molar conductance. The formula{[(Ni)3(HLn)2(µ-OAc)2(OAc)4]n has been proposed on the basis of analytical and various physico-chemical data. The hydrazone is bonded to the metal ion in bis-tetradentate fashion through carbonyl oxygen, NH(hydrazone), NH(rhodanine) and sulphur (thione rhodanine) groups as inferred from IR and 1H NMR spectra. The present study demonstrates perfectly an application of IR spectra and molecular modeling in revealing not only the multiple inter/intramolecular of π – π stacking among the aromatic groups as well as the hyDROPhobic interactions among hydrogen bonding species between hydrazide moieties involving in a series of novel hydrazide based azo drug derivatives.