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Group 8-10 Complexes Of Pyridyl-Phosphinimines And Chiral Bis-Diiminophosphoranes., Ramadan. Altwer
Group 8-10 Complexes Of Pyridyl-Phosphinimines And Chiral Bis-Diiminophosphoranes., Ramadan. Altwer
Electronic Theses and Dissertations
A group of exocyclic pyridyl-phosphinimine ligands have been prepared in excellent yields by oxidizing trip henylphosphine with 2-azidomethylpyridines. These ligands reacted with group 8--10 transition metals to form various late transition metal complexes (e.g. [Ph3P=NCH2(2-Py)]NiBr 2 36) which have been characterized and evaluated for olefin polymerization activity. We found that these complexes are not active for ethylene polymerization or oligomerization. In a similar sense, nickel complexes 55 and 56 were synthesized by the reaction of nickel dihalide with a chiral bis-diiminophosphorane ligands. The corresponding ligand was prepared by deprotonation of R-2,2' -diamino-1,1'-binaphthalenetriphenyldibromide by a strong base. The complexes were seemed …
Group Iv Phosphinimide Complexes In Catalysis., Emily Hollink
Group Iv Phosphinimide Complexes In Catalysis., Emily Hollink
Electronic Theses and Dissertations
Significant progress has been made in various aspects of the chemistry of Group IV phosphinimide complexes, particularly in their use as highly active catalysts for olefin polymerization upon activation by an appropriate Lewis acid. Advances in synthetic methods have provided routes for the preparation of phosphinimide amide inorganic and organometallic products via metathesis or protonation methods. Testing of TiCp(NPtBu 3)X2 (X = Cl, Me, NMe2) as hydroamination catalysts has shown that these complexes are inactive for this purpose under the conditions employed. In addition, numerous synthetic endeavours have revealed that the titanium phosphinimide complexes are reluctant to form isolable imide …
Surface-Enhanced Vibrational Spectroscopy Of Diphenyl Sulfide And Diphenyl Disulfide On Films And Colloids, And The Single-Molecule Detection Of Perylene Dye On Silver And Gold Colloids., Ben Issa M. Ali. Tolaieb
Surface-Enhanced Vibrational Spectroscopy Of Diphenyl Sulfide And Diphenyl Disulfide On Films And Colloids, And The Single-Molecule Detection Of Perylene Dye On Silver And Gold Colloids., Ben Issa M. Ali. Tolaieb
Electronic Theses and Dissertations
In this work, colloidal particles of gold and silver are used as enhancing substrates to study behavior of organic sulfides and a perylene derivative butylimido, butyleneamine perylene (nBu-PTCDA-(CH2) 4-NH2) adsorbed on metal particles using surface-enhanced resonance Raman scattering (SERRS) or SERS. In addition, the SERS spectra of the adsorbed species formed by diphenyl disulfide and diphenyl sulfide (DPDS, DPS) on evaporated silver and gold island thin films were obtained. The SERS vibrational spectra of both DPDS and DPS are discussed and the vibrational assignments of the fundamental modes were aided with an ab-initio calculations using Density Functional Theory (DFT) at …
Syntheses And Applications Of Group Vi And Viii-X Heterocyclic-Phosphinimine Complexes., Liam P. Spencer
Syntheses And Applications Of Group Vi And Viii-X Heterocyclic-Phosphinimine Complexes., Liam P. Spencer
Electronic Theses and Dissertations
A class of phosphinimine-based group VI and VIII-X late transition metal (LTM) complexes has been synthesized and evaluated for olefin polymerisation activity. The phosphinimine ligand has been designed to incorporate an imine moiety; a functional group which has been successfully applied in very active LTM olefin catalytic systems. Heterocycles, such as pyridine and imidazole are used to accomplish the integration of an imine group into the ligand. Phosphines employing the heterocyclic group are oxidized by phenyl azides in excellent yields to form phosphinimine ligands. These phosphinimine ligands react with several LTM's, the complexes of which are identified by single crystal …
Down Regulation Of Gene Expression In Toxoplasma Gondii By Engineered Delta Ribozymes., Ju. Sheng
Down Regulation Of Gene Expression In Toxoplasma Gondii By Engineered Delta Ribozymes., Ju. Sheng
Electronic Theses and Dissertations
Delta ribozyme is a RNA enzyme derived from the genome of hepatitis delta virus (HDV). It can specifically cleave a RNA substrate and is the only ribozyme that can function naturally in human cells. These properties make the delta ribozyme attractive as a gene modulator. Toxoplasma gondii, a pathogenic parasite to humans and pets, has been used for genetic studies. Genes encoding uracil phosphoribosyltransferase (UPRT) and hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT), which are the operative enzymes of the pyrimidine and purine salvage pathway, respectively, in T. gondii , were chosen for the study of the down regulation effect of delta ribozymes. Different …
Olefin Polymerisation Using Titanium Phosphinimide Catalysts., Steven N. Clemens
Olefin Polymerisation Using Titanium Phosphinimide Catalysts., Steven N. Clemens
Electronic Theses and Dissertations
Homopolymers of 1-hexene, random copolymers of 1-hexene and 1,5-hexadiene, and block copolymers of ethylene and 1-hexene have been prepared at sub-ambient temperatures using Cp(tBu3PN)TiMe2 ( 34) and studied. In addition, the polymerisation of 1-hexene by ( 34) has been investigated for its potential as a living polymerisation system. Analysis of the poly(1-hexene) produced by (34) via 13C NMR spectroscopy reveals that the polymer contains an unusually high degree of 2,1 enchainments, with approximately one in five insertions being reversed relative to the previous one. This suggests that the coordination sphere in (34) is more open than in metallocene catalysts. However, …
Electrochemistry And Spectroscopy Of Energy Conversion And Polynuclear Aromatic Materials., Maryam. Nazri
Electrochemistry And Spectroscopy Of Energy Conversion And Polynuclear Aromatic Materials., Maryam. Nazri
Electronic Theses and Dissertations
The field of materials chemistry is becoming increasingly important in many technological disciplines, including batteries, fuel cells, hydrogen storage materials, and application of poly-nuclear aromatic compounds in solar cells, color copiers, sensors, and catalysis. This multidisciplinary research work focuses on the development, understanding, and characterization of novel materials for advanced lithium batteries and a unique series of polyaromatic compounds for application in solar cells and color copiers. A general overview of materials and techniques used in this work is presented, including the electrochemistry, spectroscopy, thermal analysis, and x-ray diffraction. A unique electrochemical procedure based on carbon paste microelectrode was applied …
Characterization Of A Novel Human Cap2 Interacting Protein: Neuronal Calcium Binding Protein 1 (Necab1)., Emilio P. Mottillo
Characterization Of A Novel Human Cap2 Interacting Protein: Neuronal Calcium Binding Protein 1 (Necab1)., Emilio P. Mottillo
Electronic Theses and Dissertations
The actin cytoskeleton is implicated in numerous processes such as cellular division, migration, endocytosislexocytosis, and more recently synaptic plasticity. Important players in controlling cytoskeletal rearrangements are the Cyclase Associated Proteins (CAPs) which are thought to link cell signalling to the dynamics of the actin cytoskeleton, via sequestration of monomeric actin subunits. CAPs are conserved throughout evolution and possess conserved functional domains. Previous studies have suggested a link between CAP proteins and vesicle trafficking and this study focussed on characterizing binding partners of human CAPs. Using a two hybrid screen of a human adult brain cDNA library, a novel human CAP …
Chemical, Biochemical, And Cellular Aspects Of S-Nitrosothiols., Shirin. Akhter
Chemical, Biochemical, And Cellular Aspects Of S-Nitrosothiols., Shirin. Akhter
Electronic Theses and Dissertations
Nitric oxide is involved in many physiological processes including vascular control, immune responses and neurotransmission under physiological conditions. Many functions of NO are triggered by the formation of its metabolite, S-nitrosothiol. S-nitrosothiols play an important role in the delivery, storage and transport of NO. In addition, they regulate the activity of a variety of proteins and enzymes. The first part of my study is focused on studying the regulatory role of S-nitrosothiol. In this study, S-nitrosothiols including S-nitrosoglutathione (GSNO) have been demonstrated to regulate the activity of a key protein in plasma, fibrinogen, without chemically modifying it. GSNO and a …
Metallated Group Ix And Group X Phosphinimine Complexes., Katie Tak-Kwan. Chan
Metallated Group Ix And Group X Phosphinimine Complexes., Katie Tak-Kwan. Chan
Electronic Theses and Dissertations
The focus of this research has been the preparation of late transition metal phosphinimine complexes. The thesis herein describes the synthesis of a series of monomeric Group IX phosphinimine complexes. [RhCOD(o-C 6H4PPh2NR)] (R = 2,6-C6H3(CH 3)2 44, 2,6-C6H3 iPr2 45, 3,5-C6H3(CH 3)2 46 and Ph 47) were prepared via salt metathesis under mild conditions. The analogous complexes [Rh( o-C6H4PPh2NPh)(Ph2PCH 2CH2PPh2)] 52 and [IrCOD( o-C6H4PPh2NPh)] 53 were also readily prepared by similar methods. Reactivity studies were performed on these complexes. Unexpectedly, complexes 46, 47, 52 and 53 underwent oxidative addition of methylene chloride. However, when steric bulk was introduced on the …