الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Many studies mentioned that our world will be almost run out of fossil
oil in about 50 years. So, there are crucial needs to search for alternatives. The most important candidate for that is renewable energy and this due to
several factors including economy, environment, and security. In the
meanwhile, one of the biggest technological challenges faced by the
chemists and scientists these years is the development of renewal energy.
However, many scientists believe that water in presence of sunlight and
some cheap catalysts can be split and produce H2 fuel. So, these years our
world is in competition to prepare some complexes that can be tried and
used as catalysts to fulfill that job.
On the other hand, it is well known that N, O, and S atoms play an
important role in coordination chemistry. Moreover, 1,2,4-triazole
derivatives have different bonding modes concerning their coordination to
the metal centers, and they have been proven that they are biologically active
and some of them might be used as antibacterial and antifungal reagents.
The previously mentioned factors motivated and forced us to do
chemistry in these two different areas. It is noteworthy that this dissertation
entitled “Physicochemical Studies on Some Schiff Bases and Their
Complexes with Some Transition Metal Ions” comprises three chapters.
Chapter 1 (General introduction) comprises the introduction which
presents brief accounts on the importance of the Schiff base ligands, their
preparation, and their metallation by using different routes. This introduction
also includes some literature survey on acyclic Schiff bases, and triazole
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derivatives, and their complexes as well. Lastly, this chapter contains some
applications of the Schiff base ligands and their complexes.
Chapter 2 (Studies on synthesis of a new tripodal ligand and its
metallation) contains a very short introduction on renewable energy and the
main players in this field and the idea of how water can be used as a fuel.
This chapter also includes the used chemicals and equipment, along with the
experimental methods used for preparation and purification of the new
tripodal Schiff base ligand that we made. It is noteworthy that the tripodal
ligand was synthesized through four steps, and this ligand has a new system
regarding to the functional groups that it carries. However, the percentage
yield obtained for the tripodal ligand was 91.8% and it is very important to
mention that this ligand was prepared from cheap chemically starting
materials. Furthermore, many methodologies have been tried to metallate
this new ligand. The only methodology that could do this was the one that
the dimanganese organometallic precursor has been used. Plus, the
percentage yield obtained for the dimanganese complex was about 83.20%.
The identification of the synthesized dimanganese complex, by using the
elementary, magnetism as well as spectroscopic (IR, 1H-NMR, and UV-Vis)
measurements, was presented and discussed. However, the preparation of
some metal precursors was explained and discussed as well. Finally, the
conductometric and potentiometric titrations of the new ligand with Mn2+
ions were presented and discussed.
Chapter 3 (Studies on synthesis of some Schiff base-Triazole
ligands and their metallation) includes a brief introduction on the
importance of the triazole derivatives and their complexes in coordination
chemistry and in our life as well. This chapter also includes the used
deutrated solvents and equipment, and the experimental procedures used for
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preparation and purification of five triazole Schiff base ligands. These
ligands were prepared through four steps to give the percentage yields
ranging from 78.1% to 85.3%. The characterization of those five ligands was
presented and discussed. The effect of polarity of the solvents was studied
very briefly. Plus, the pKas of the ligands were determined using different
methods. Moreover, the chelation of the synthesized Schiff base ligands with
V3+, Cr3+, Mn2+, and Fe3+ ions are studied in solution and solid state.
However, studies in solution included conductometric titration revealed that
the stoichiometry of the type 2:1, 1:1, 1:2 (M:L) are detected. Additionally,
potentiometric titration of these ligands with the previously mentioned metal
ions is performed in a medium of hydrochloric acid and potassium chloride.
The half interpolation is applied to determine the proton-ligand stability
constants, and both the stepwise formation constants pK, and the overall
formation constants of the produced chelates. On the other hand, studies in
solid state which include synthesis of some neutral complexes have been
achieved. Plus, the synthesis of those neutral complexes has been discussed
in details in this chapter, and the percentage yields obtained for the
synthesized complexes are in the range from 50.6% to 80.4%. The
identification of the synthesized complexes by using the elementary,
magnetism, molar conductivity, and spectroscopic (IR, 1H-NMR, and UVVis
(in DMF, and in Nujol mull)) measurements was presented and
discussed.