Jessy Emmanuel; Dr.Prathapachandra Kurup,M R(Cochin University Of Science And Technology, July 26, 2012)
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Abstract:
Supra molecular architectures of coordination complexes of liydrazones
through non covalent interactions have been explored. Molecular self—assernbly
driven by weak interactions such as hydrogen— bonding, K '”T[, C-1-I‘ "TE, van
der Waals interactions, and so forth are currently of tremendous research
interest in the fields of molecule based materials. The directional properties of
the hydrogembonding interaction associate discrete molecules into aggregate
structures that are sufficiently stable to be considered as independent chemical
species. Chemistry can borrow nature’s strategy to utilize hydrogen-bonding as
Well as other noncovalent interactions as found in secondary and tertiary
structures of proteins such as the double helix folding of DNA, hydrophobic
selflorganization of phospholipids in cell membrane etc. In supramolecular
chemistry hydrogen bonding plays an important role in forming a variety of
architectures. Thus, the wise modulation and tuning of the complementary sites
responsible for hydrogen—bond formation have led to its application in
supramolecular electronics, host-guest chemistry, self-assembly of molecular
capsules, nanotubes etc. The work presented in this thesis describes the synthesis and
characterization of metal complexes derived from some substituted
aroylhydrazones. The thesis is divided into seven chapters.
Description:
Department of Applied Chemistry, Cochin University of Science and
Technology
Bessy Raj, B N; Dr.Prathapachandra Kurup,M R(Cochin University of Science and Technology, February , 2009)
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Abstract:
The present work deals with the complexation of Schiff
bases of aroylhydrazines with various transition metal ions. The hydrazone
systems selected for study have long 7I:-delocalized chain in the ligand molecule
itself, which get intensified due to metal-to-ligand or ligand-to-metal charge
transfer excitations upon coordination. Complexation with metal ions like copper,
nickel, cobalt, manganese, iron, zinc and cadmium are tried. Various spectral
techniques are employed for characterization. The structures of some complexes
have been well established by single crystal X-ray diffraction studies. The nonIinaer
optical studies of the ligands and complexes synthesized have been studied
by hyper-Rayleigh scattering technique.The work is presented in seven chapters and the last one deals with
summary and conclusion. One of the hydrazone system selected for study proved
that it could give rise to polymeric metal complexes. Some of the copper, nickel,
zinc and cadmium complexes showed non-linear optical activity. The NLO
studies of manganese and iron showed negative result, may be due to the inversion
centre of symmetry within the molecular lattice.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology
Vineetha,C P; Mohammed Yusuff, K K(Department of Applied Chemistry, Faculty of Science, 2002)
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Abstract:
The thesis deals with the synthesis, characterization and catalytic activity studies of some new Fe (III), Co (II), Ni (II) and Cu (II) complexes of hydrazones and their zeolite encapsulated analogues. Hydrazones have diverse applications in biological, non-biological and biochemical front. During the present study three hydrazone types of ligands namely, acetylacetone- 2-hydroxyphenylhydrazone (APAcAc), acetoacetanilide- 2-hydroxyphenylhydrazone (APAcAcA) and acetoacetanilide-3,5-dihydro-2,4-dione pyrimidylhydrazone (AUAcAcA) were synthesized by diazotization of primary amine and coupling with compounds containing active methylene group. First part of the thesis deals with the synthesis of Fe, Co, Ni and Cu complexes using three hydrazone types of ligands are given. Details regarding the characterization of these complexes with a view to establishing the molecular structures are presented in this part. The other part contains the method of encapsulation of these complexes in zeolite cavities and their characterizations of the encapsulated metal species are described. A comparitive account of the catalytic activities of the pure and encapsulated complexes for cyclohexanol oxidation was also carried out.
Joseph, Babitha; Dr Prathapachantra Kurup, M R(Cochin University of Science And Technology, November 20, 2014)
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Abstract:
The ability of aroylhydrazones to bind with transition metals is a
developing area of research interest and the coordinating properties of
hydrazones can be tuned by the appropriate choice of parent aldehyde or
ketone and the hydrazide. So in the present work we selected four different
aroylhydrazones as principal ligands. Introduction of heterocyclic bases like
1,10-phenanthroline, 2,2′-bipyridine, 3-picoline and pyridine leads to the
syntheses of mixed ligand metal chelates which can cause different bonding
modes, spectral properties and geometries in coordination compounds. The
importance of aroylhydrazones and their complexes in various fields and their
interesting coordinating properties stimulate our interest in the investigation of
transition metal chelates with four different aroylhydrazones. The aroylhydrazones
selected are 4-benzyloxy-2-hydroxybenzaldehyde-4-nitrobenzoylhydrazone
dimethylformamide monosolvate, 5-bromo-2-hydroxy-3-methoxybenzaldehyde
nicotinoylhydrazone dihydrate methanol monosolvate, 4-diethylamino-2-
hydroxybenzaldehyde nicotinoylhydrazone monohydrate and 2-benzoylpyridine-
4-nitrobenzoylhydrazone. The selection of 4-benzyloxy-2-hydroxybenzaldehyde-
4-nitrobenzoylhydrazone was based on the idea of developing ligands having
D-π-A general structure, so that the proligand and metal complexes exhibit
NLO activity. Hence it is interesting to explore the coordinating capabilities
of the synthesized hydrazones and to study the NLO activity of hydrazones
and some of the metal complexes.
Sreeja,P B; Prathapachandra Kurup, M R(Department of Applied Chemistry,Faculty of Science, 2004)
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Abstract:
This study concentrates the chemical properties of hydrazones due to its chelating capability and their pharmacological applications. Studies cover the preparation of different acid hydrazones and their structural studies and studies on their antimicrobial activity, synthesis and spectral characterization of different complexes of copper oxovanadium, manganese, nickel etc. Effect of incorporation of heterocyclic bases to the coordination sphere, change in the biological activity of acid hydrazones upon coordination, development of X-ray quality single crystals and its X-ray diffraction studies, studies on the redox behavior of the coordinated metal ions and correlation between the stereochemistry and biological activities.
Mini, Kuriakose; Dr.Prathapachandra Kurup,M R(Cochin University of Science & Technology, December , 2006)
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Abstract:
The present work deals with the complexation of Schiff
bases of aroylhydrazides with various transition metal ions. The hydrazone
systems selected for study are capable of forming bridged polymeric structures
which is one of the fascinating subjects in the crystal engineering of coordination
polymers owing to their attractive new topologies and intriguing structural
features. Complexation with metal ions like copper, manganese, vanadium,
nickel, palladium, zinc and cadmium are tried. Various spectral techniques are
employed for characterization. The structures of some complexes have been well
established by single crystal X-ray diffraction studies.The work is presented in seven chapters and the last section deals with
summary and conclusion. The studies reveal that the aroylhydrazone systems vary
in their geometrical configuration depending on the substituents. The coordination
modes of the ligands also differ upon chelating with metal ions. One of the
hydrazone system selected for study proved that it could give rise to polymeric
metal complexes.
Description:
Dept.of Applied Chemistry,Cochin University of Science and Technology