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1
Zini, Simone. "Synthesis of manganese organometallic complexes." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22235/.
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Il presente lavoro di tesi si inserisce in un progetto di ricerca volto alla sintesi di nuovi complessi di metalli di transizione per lo sviluppo di catalizzatori da impiegare in reazioni di catalisi omogenea. In particolare il mio progetto si è concentrato sulla sintesi di complessi organometallici di manganese con leganti carbenici N-eterociclici (NHC). La scelta dei leganti è stata effettuata in modo tale da poter avere leganti chelanti NHC di tipo MIC (mesoionic carbene) sintetizzati tramite cicloaddizione tra un alchino ed un azide catalizzata da rame (CuAAC) e N-alchilazione. Lo studio di questi complessi a base di manganese è ancora tutt’oggi agli albori, leganti NHC vengono molto utilizzati grazie alla possibilità di variarne le proprietà steriche ed elettroniche e alla possibilità di formare legami forti con quasi tutti i metalli. Il manganese è stato scelto poiché un elemento abbondante, poco tossico e poco costoso.
The present thesis work is part of a research project aimed at the synthesis of new transition metal complexes to be used in homogeneous catalysis reactions. In particular my project focused on the synthesis of manganese organometallic complexes with N-heterocyclic carbene ligands (NHC). The choice of ligands was carried out to have NHC chelating ligands of the class of MIC (mesoionic carbene). These ligands are synthesized by cycloaddition between alkyl and azide with a copper-catalyzed reaction (CuAAC) and N-alkylation in order to obtain MIC after deprotonation. The study of these manganese-based complexes is still in its infancy today, NHC ligands are widely used thanks to the possibility of varying their steric and electronic properties and the possibility of forming strong bonds with almost all metals. The choice of manganese was made because is an abundant, low-toxic and inexpensive element.
2
Lee, Peter D. "Organometallic synthesis in supercritical fluids." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336862.
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Berridge, Rory. "The synthesis of novel organometallic materials." Thesis, Sheffield Hallam University, 2001. http://shura.shu.ac.uk/19349/.
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Due to their highly interesting electroactive properties, complexes based on the sulphur heterocycle DMIT have been studied extensively for several decades. The literature is abundant with materials exhibiting semiconducting and metallic properties and up to early 2000 there are eight examples of DMIT based superconductors. In the case of the DMIT complexes, previous work has been constrained to the variation of the transition metal and/or the counter-anion. The work herein concerns the synthesis of a novel series of electroactive ligands, similar to the well-known DMIT species. In contrast to the DMIT ligand, our target derivatives incorporate two thioether and two dithiolate environments as the overall chelating entity. The thioether functionalities are linked via suitable spacer groups and this feature should present a major advantage over traditional DMIT complexes, by adding solubility and synthetic versatility to the overall nature of the complex. In addition to the metal complexes based on DMIT ligands, charge transfer (CT) halogen adducts of these DMIT ligands and their synthetic intermediates are described, providing highly interesting and novel solid state structures and atom-to-atom inter- and intra-molecular interactions.
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Abdelsalam, Mansour. "Synthesis of piperidines using organometallic chemistry." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4069/.
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Ashcroft, R. C. "Organometallic precursors for pillared clay synthesis." Thesis, Aston University, 1993. http://publications.aston.ac.uk/9773/.
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The synthetic hectorite, laponite has been used within the paper industry to produce mildly conducting paper for use in electrographic printing. The aim of this research was to modify laponite in order to improve the electrical conductivity. In a continuation of a previous investigation involving organotin intercalation of laponite, the organotin precursor (p-CH3,OC6H4)4Sn was synthesised and characterised using Mass Spectroscopy, Infrared Spectroscopy and elemental analysis. Results of intercalation with this compound and a range of organobismuth and organoantimony compounds suggested that a halide content within the precursor was necessary for improvement in conductivity to be observed. Organometallic intercalation of a range of organotellurium compounds with laponite provided evidence that a hydrolysis reaction on the clay surface followed by the release of hydrochloric acid was an important first step if a reaction was to occur with the clay. Atomic Absorption Spectroscopy studies have shown that the acid protons underwent exchange with the interlayer sodium ions in the clay to varying degrees. Gas-liquid Chromatography and Infrared Spectroscopy revealed that the carbon-tellurium bond remained intact. Powder X-ray diffraction revealed that there had been no increase in the basal spacing. The a.c. conductivity of the modified clays in the form of pressed discs was studied over a frequency range of 12Hz - 100kHz using two electrode systems, silver paste and stainless steel. The a.c. conductivity consists of two components, ionic and reactive. The conductivity of laponite was increased by intercalation with organometallic compounds. The most impressive increase was gained using the organotellurium precursor (p-CH3OC6H4)2TeCl2. Conductivity investigations using the stainless steel electrode where measurements are made under pressure showed that in the case of laponite, where poor particle-particle contact exists at ambient pressure, there is a two order of magnitude increase in the measured a.c. conductivity. This significant increase was not seen in modified laponites where the particle-particle contact had already been improved upon. Investigations of the clay surface using Scanning Electron Microscopy suggested that the improvement in particle-particle contact is the largest factor in the determination of the conductivity. The other important factor is the nature and the concentration of the interlayer cations. A range of clays were synthesised in order to increase the concentration of sodium interlayer cations. A sol-gel method was employed to carry out these syntheses. A conductivity evaluation showed that increasing the concentration of the sodium cations within the clay led to an increase in the conductivity.
6
Lee, Linda I.-Lin. "Synthesis and reactivity of organometallic enediynes /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3025940.
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7
Atefi, Farzad. "Synthesis and reactions of organometallic porphyrins." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/17563/1/Farzad_Atefi_Thesis.pdf.
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This thesis reports progress in three major aspects of σ-bonded organometallic porphyrins that are described in the published papers found in chapters 4, 5 and 6. meso-Iodoporphyrins, which were prepared in a rapid, selective and high yielding methodology from the respective 1-palladioporphyrins or bromoporphyrins, are important starting materials for further functionalisations of porphyrins. Their utility was confirmed in a palladium-catalysed coupling reaction and this novel synthetic strategy could potentially be applied for iodine/bromine exchange on other organic substrates..
A 1-palladioporphyrin was also utilised to optimise the reaction conditions leading to the formation of porphyrinylphosphine oxides. This synthetic strategy simplified the challenging optimisation of the palladium-catalysed reaction and has great potential to be applied in other catalytic processes. Subsequently a suite of porphyrinylphosphine oxides was prepared under the optimised catalytic conditions. These macrocycles, which represent a new class of porphyrins, were isolated cleanly in very high yields. Detailed spectroscopic investigations as well as X-ray single crystal analysis demonstrated their structures unambiguously and established their potential as ligands for supramolecular chemistry.
The coordinating properties of phosphine oxides in general and porphyrinylphosphine oxides in particular, towards Mg(II) centred porphyrins were examined in further experiments. Triphenylphosphine oxide showed a strong affinity towards Mg(II) porphyrins and the calculated displacement constant of 5.3 × 105 M-1 was two orders of magnitude larger than any other Mg(II) porphyrin-ligand binding constant reported thus far. Di- and triporphyrin arrays consisting of Mg(II) porphyrin coordinated to free base and Ni(II) porphyrinyl mono- and bis-phosphine oxides were also prepared in high yields. Spectroscopic studies indicated that these porphyrin oligomers exhibit strong inter-porphyrin electronic interaction.
A Mg(II) porphyrinylphosphine oxide dimer was also isolated in a satisfactory yield. The large self-association constant of 5.5 × 108 M-1 confirmed the strong affinity of porphyrinylphosphine oxides towards Mg(II) porphyrins and established these complexes as the first strongly bound synthetic Mg(II) porphyrin analogues of the "special pair" of the photosynthetic reaction centre.
8
Atefi, Farzad. "Synthesis and reactions of organometallic porphyrins." Queensland University of Technology, 2007. http://eprints.qut.edu.au/17563/.
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This thesis reports progress in three major aspects of σ-bonded organometallic porphyrins that are described in the published papers found in chapters 4, 5 and 6. meso-Iodoporphyrins, which were prepared in a rapid, selective and high yielding methodology from the respective 1-palladioporphyrins or bromoporphyrins, are important starting materials for further functionalisations of porphyrins. Their utility was confirmed in a palladium-catalysed coupling reaction and this novel synthetic strategy could potentially be applied for iodine/bromine exchange on other organic substrates..
A 1-palladioporphyrin was also utilised to optimise the reaction conditions leading to the formation of porphyrinylphosphine oxides. This synthetic strategy simplified the challenging optimisation of the palladium-catalysed reaction and has great potential to be applied in other catalytic processes. Subsequently a suite of porphyrinylphosphine oxides was prepared under the optimised catalytic conditions. These macrocycles, which represent a new class of porphyrins, were isolated cleanly in very high yields. Detailed spectroscopic investigations as well as X-ray single crystal analysis demonstrated their structures unambiguously and established their potential as ligands for supramolecular chemistry.
The coordinating properties of phosphine oxides in general and porphyrinylphosphine oxides in particular, towards Mg(II) centred porphyrins were examined in further experiments. Triphenylphosphine oxide showed a strong affinity towards Mg(II) porphyrins and the calculated displacement constant of 5.3 × 105 M-1 was two orders of magnitude larger than any other Mg(II) porphyrin-ligand binding constant reported thus far. Di- and triporphyrin arrays consisting of Mg(II) porphyrin coordinated to free base and Ni(II) porphyrinyl mono- and bis-phosphine oxides were also prepared in high yields. Spectroscopic studies indicated that these porphyrin oligomers exhibit strong inter-porphyrin electronic interaction.
A Mg(II) porphyrinylphosphine oxide dimer was also isolated in a satisfactory yield. The large self-association constant of 5.5 × 108 M-1 confirmed the strong affinity of porphyrinylphosphine oxides towards Mg(II) porphyrins and established these complexes as the first strongly bound synthetic Mg(II) porphyrin analogues of the "special pair" of the photosynthetic reaction centre.
9
Qin, J. "Studies in organometallic solid state chemistry." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379942.
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Stewart, A. S. J. "Organometallic derivatives of amino acids and peptides." Thesis, Robert Gordon University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376684.
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Moss, James Edward. "The Synthesis and Organometallic Chemistry of NonamethyIfluorene." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491509.
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The focus of this thesis is the synthesis and organometallic chemistry of the nonamethylfluorene ligand (Flu*). Chapter One summarises the properties and uses of the fluorene molecule and the incorporation of both the neutral and deprotonated forms of the ligand into organometallic complexes. The chapter concludes with a discussion of the properties that are bestowed upon organometallic compounds containing fully methylated ligands, detailing the need for nonamethylfluorene. Chapter Two describes a relatively high yielding total synthesis of the fully methylated fluorene, Flu*H, using techniques and equipment that are amenable to most laboratories. All but one of the precursors have been crystallographically characterised, and this analysis shows in all cases a twisted fluorene skeleton due to unfavourable close contacts between methyl groups. Octamethyldibenzofulvene has been radically coupled to form an ethane bridged ligand set using a technique not previously used for fluorene. Chapter Three documents the interaction of the neutral polymethylated fluorenes Flu*H and Flu'H with Cr, Fe and Mn. Both mono and bimetallic complexes have been isolated, and many have been crystallographically characterised. In the monometallic case, haptotropic shifts are seen for both Fe and Cr, but deprotonation of the Mn complex yields a previously unknown coordination mode of fluorene. DFT studies of the protonated and deprotonated bimetallic Cr complexes give an indication of the mode of metal-ligand binding, and this is confirmed by a crystallographic study. Bimetallic Fe complexes have been shown to be active catalysts in the dechlorination of PCBs, toxic environmental pollutants. Chapter Four describes the synthesis of Flu* transfer reagents; the crystal structure of the lithiate Flu*Li.TMEDA has been determined and shows a twisted fluorene skeleton. DFT studies on both the protonated and deprotonated, methylated and nonmethylated fluorenes have been performed to examine the distribution of charge in these molecules. Chapter Five discusses the interaction of the transfer reagents described in Chapter Four with a variety of metal precursors. Reasons for the observed lack of stability of Flu* containing complexes are given. The synthesis and molecular structure of complexes of Zr and In are reported; the Zr compound represents the first crystallographically characterised mono-fluorenyl Zr complex not containing a supporting heteroatom. The interaction of EBFlu*2- with metal precursors is also examined. Chapter Six describes the synthesis of mono and bimetallic Co complexes of octamethylfluorenone. Crystal structure determinations show that the Cp*Co fragment dearomatises both six membered rings in the fluorenone, only the second example ofthis type ofcoordination. Chapter Seven contains experimental procedures, Chapter Eight details characterising data for all new compounds, and crystallographic data in the form of CIF files may be found in the electronic Appendix, found on the compact disc at the back of this thesis.
12
Beck, Victoria Holly. "Synthesis and characterisation of bimetallic organometallic complexes." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403935.
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Meng, Weidong. "Organometallic approaches to the synthesis of tridachiapyrones." Thesis, University of East Anglia, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.256766.
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Alshammari, Mohammed. "Use of organometallic intermediates in organic synthesis." Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/45471/.
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Chapter One: Chapter one describes a historical overview and the practical consideration of lithiation reactions and highlight of some of the factors that could influence the site of lithiation. It also provides reviews of the directed and side-chain lithiation of substituted aromatics. Chapter Two: Chapter two deals with lithiation of N′-phenethyl-N,N-dimethylurea with three equivalents of t-BuLi in THF at –78 °C followed by reaction with various electrophiles to give side-chain substituted products due to lithiation and substitution at the CH2 next to the phenyl ring (α-lithiation). The 2-lithio isomer can be obtained via Br–Li exchange of 2-bromo derivative using MeLi followed by t-BuLi in THF at –78 °C. The lithium reagents thus obtained react with various electrophiles to give the corresponding 2-substituted derivatives in excellent yields. Lithiation of N′-(3-phenylpropyl)-N,N-dimethylurea takes place on the α-CH2 with t-BuLi at 0 °C. On the other hand, lithiation of N′-(4-phenylbutyl)-N,N-dimethylurea with t-BuLi at 0 °C takes place on one of the methyl groups of the urea unit. Chapter Three: Chapter three includes lithiation of N'-(2-(2-methylphenyl)ethyl)-N,N-dimethylurea with three equivalents of n-BuLi in THF at 0 °C followed by reaction with various electrophiles to give side-chain products in excellent yields due to α-lithiation. Similarly, lithiation of the pivalamide derivative followed by reaction with benzophenone as a representative electrophile gave the corresponding α-substituted product in high yield. Surprisingly, no products resulting from lateral lithiation were observed under the conditions tried, which sharply contrast with the reported results for lateral lithiation of the carbamate derivative. Chapter Four: In this chapter, N-(2-(4-methoxyphenyl)ethyl)amine derivatives are reported to undergo directed ortho-lithiation next to the directing group with n-BuLi at 0 ºC, followed by treatment with various electrophiles, to give high yields of the corresponding substituted products. This contrasts sharply with the earlier results for the α-substitution of the pivaloyl derivative using t-BuLi at a lower temperature. Chapter Five: Chapter five includes variations in the site of lithiation of N-acyl-3-(aminomethyl)pyridine derivatives with different N-substituents using different lithiating reagents. Ring lithiation has been achieved by the use of t-BuLi at -78 °C followed by reaction with various electrophiles to give the corresponding 4-substituted products in high yields. On the other hand, the reaction was regioselective towards the side-chain when LDA was used as the lithium reagent at -20 to 0 °C. A mixture of ring and side-chain substitution products was obtained when n-BuLi was the lithium reagent. Chapter Six: Chapter six investigates the use of various chiral ligands containing different coordinating groups in Matteson homologation. Some stereoselectivity (de = 2-52%) was obtained depending on the type of chiral catalyst used. The best %de (52%) was obtained when Yb(OTf)3 as a Lewis acid and (1R,2R)-1,2-bis((R)-2,2-dimethyl-1,3-dioxolan-4-yl)ethane-1,2-diol as a chiral ligand were used in combination. However, significant %de (46%) could be obtained with the diol chiral ligand in the absence of the Lewis acid, which is very interesting and open windows for further improvement.
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Murphy, Vincent John. "Synthesis and characterisation of organometallic molecular materials." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357440.
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Dickerson, Bryan Douglas. "Organometallic Synthesis Kinetics of CdSe Quantum Dots." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27322.
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CdSe quantum dots produced by organometallic synthesis are useful as tunable emitters for photonic devices and as multi-colored protein markers for biomedical imaging, applications requiring bright and narrow emission. A diffusion-limited model helped monitor growth rates via photoluminescence and absorbance spectroscopy, in order to characterize synthesis kinetics in stearic acid, dodecylamine, and in trioctylphosphine oxide. The nucleation rate increased with Se concentration, while the growth rate followed the Cd concentration.
Emission peak widths, emission redshift rates, nanocrystal growth rates, and reactant concentrations all decreased to a minimum when emission reached the critical wavelength, at a reaction completion time, tc. The temperature dependence of 1/tc and of redshift rates followed Arrhenius behavior governed by activation energies, which were tailored by the choice of solvent. Synthesis in solvents, such as stearic acid, with lower activation energies produced faster initial nanocrystal growth and longer critical wavelengths. The highest photoluminescence quantum yield was generally at wavelengths shorter than the critical wavelength, when moderate growth rates enabled surface reconstruction while precursors were still available.Ph. D.
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Lovett, Victoria Jane. "Synthesis of amino acids using organometallic chemistry." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/5416/.
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Lawrence, Heather Bunting Elizabeth. "Organometallic compounds with non-linear optical properties." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276835.
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Rumble, Sarah Louise Chemistry Faculty of Science UNSW. "The synthesis of amines and imines organometallic catalysts." Awarded by:University of New South Wales. School of Chemistry, 2005. http://handle.unsw.edu.au/1959.4/23422.
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This thesis describes investigations into the catalysed syntheses of amines and imines using organoiridium and organorhodium complexes with N-donor ligands as the catalysts. These catalysed syntheses were achieved via hydroamination, hydrosilylation, and hydrogenation reactions, as well as tandem hydroamination/imine reduction reactions. An in situ catalysis study found that the most active catalysts for the hydroamination of 4-pentyn-1-amine (1) to give 2-methyl-1-pyrroline (4) were formed from a combination of catalyst components that resulted in an electron deficient metal centre, indicating that an alkyne binding mechanism was most likely. The kinetics of the hydroamination of 4-pentyn-1-amine (1), catalysed by the complexes [Rh(bim)(CO)2][BPh4] (7), [Ir(bim)(CO)2][BPh4] (8), [Rh(bpm)(CO)2][BPh4] (9),and [Ir(bpm)(CO)2][BPh4] (10) (bpm = bis(1-pyrazolyl)methane and bim = bis(Nmethylimidazol- 2-yl)methane) were modelled and compared. The nature of the metal centre was found to have the most influence on the rate of the product release step, while the nature of the N-donor ligand was found to have the most influence on the rate of the substrate binding step. The investigation of the catalysed hydroamination of the phenyl substituted alkynylamines 5-phenyl-4-pentyn-1-amine (2), 4-phenyl-3-butyn-1-amine (13) and 2- phenyl-4-pentyn-1-amine (34) revealed a difference in catalytic activity between the rhodium and iridium complexes depending on the alkyne substituent. A series of novel rhodium(I) complexes were synthesised: [RhClCO(Mes-DAD(Me))] (38), [RhClCO(Mes-BIAN)] (22), [Rh(COD)(Mes-BIAN)][BF4] (39), [Rh2(COD)2(bmimen)](BPh4)2 (40) and [Rh2(CO)4(bmimen)](BPh4)2 (41), where Mes- DAD(Me) = biacetylbis(2,4,6-trimethylphenylimine), Mes-BIAN = bis(2,4,6- trimethylphenylimino)acenapthene and bmimen = 1,2-bis[(1-methyl-2- imidazolyl)methylene-amino]ethane. The cationic complex 40 was found to be an active hydroamination catalyst, while the neutral complexes 38 and 22 were only active in the presence of the tetraphenylborate counterion. A range of imines was found to be efficiently reduced to their respective amines via hydrosilylation or hydrogenation using the iridium(I) complex [Ir(bpm)(CO)2][BPh4] (10) as catalyst. The hydrosilylation reaction was found to be significantly faster in a protic solvent (methanol), giving the desilylated amines without the need for a desilylation step. The mechanism of this reaction was proposed to involve a monohydride iridium(I) complex as a key intermediate. The tandem hydroamination/hydrosilylation of a series of alkynylamine substrates was achieved using the iridium complexes 8 and 10, in which the iridium complex catalyses the two mechanistically distinct reactions in the one-pot. Catalysed tandem hydroamination/hydrogenation reactions were also achieved, but were less facile.
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Wallner, Olov. "Palladium-Catalyzed Synthesis and Transformations of Organometallic Compounds." Doctoral thesis, Stockholm : Dept. of Organic Chemistry, Stockholm University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-804.
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Manville, Charles. "New organic and organometallic catalysts for asymmetric synthesis." Thesis, University of Warwick, 2010. http://wrap.warwick.ac.uk/35525/.
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Monodentate phosphorus ligands based on BINOL have been synthesised and applied to metal catalysed pressure hydrogenation and conjugate addition. Novel phosphorus containing enantioselective organocatalysts have been synthesised from DPEN and proline, and studied in the Michael addition of acetone to trans-β- nitrostyrenes, with up to 96 % e.e. The optimum reaction conditions for reaction rate and enantioselectivity have been investigated. Related proline-DPEN coupled organocatalysts have been synthesised and applied to the coupling reaction between DEAD and aldehydes. The proline-DPEN coupled compounds have been investigated for uses as ligands in the ruthenium catalysed asymmetric transfer hydrogenation of ketones in an aqueous medium. The hydrogenation reactions can be performed with good conversions and up to 98% e.e.
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Stunt, R. A. "Synthesis and luminescence studies of some organometallic complexes." Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380965.
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King, Andrew John. "An organometallic approach to total synthesis of phyllanthocin." Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307326.
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Dutkiewicz, Michal Seweryn. "Organometallic neptunium complexes : synthesis, structure and reduction chemistry." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/25503.
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The aim of the work described in this thesis was to develop a more extensive knowledge of the chemistry of neptunium compounds by making rare, air- and moisture sensitive, low formal oxidation state neptunium compounds with full structural and synthetic characterization. The thesis contains three results chapters. Chapter one introduces neptunium chemistry as a background to the results presented. The first review on the molecular non-aqueous neptunium chemistry is provided and the literature reports to date discussed in the context of this. Chapter two describes exploratory synthetic and structural investigations of the organoneptunium complexes supported by the cyclopentadienyl anion, Cp = (C5H5)-, and the (trimethylsilyl)cyclopentadienyl anion, Cp' = (C5H4[Si(CH3)3])-. The syntheses of [Np(Cp)3]n and Np(Cp')3 complexes are detailed and the effect of the trimethylsilyl group of the ligand on the structure and reactivity have been investigated. Complexes were characterized by single crystal X-ray diffractometry, NMR and ATR(IR) spectroscopy. Both organoneptunium complexes were studied in reactions designed to expand the neptunium redox envelope. Notably, the complex Np(Cp')3 is reduced by KC8 in the presence of 2.2.2-cryptand to afford a product assigned as neptunium(II) complex, K(2.2.2-cryptand)[Np(Cp')3] that is thermally very unstable above approx. -10 ºC, in direct analogy to previously reported uranium, thorium and lanthanide complexes of the general formula, K(2.2.2-cryptand)[M(Cp')3]. The reaction between Np(Cp)3Cl and KCp in THF afforded the unanticipated K[NpIII(Cp)4] product as a result of a single-electron reduction presumably arising from Np–C σ-bond homolysis reactivity. This behaviour appears to be unique amongst the actinides for the An(IV)/An(III) redox couple. Chapter three focuses on oxo-bridged homo and heterometallic complexes. The reaction of NpCp3 with dioxygen afforded not only the simple oxide, (μ-O)[An(Cp)3]2, but also a small quantity of the unexpected new trinuclear oxo- neptunium(IV) compound [{(Cp3Np)(μ-O)}2{Np(Cp)2}], which interestingly contains the rare C2v-symetric [An(Cp)2]2+ structural moiety. This oxo-bridged environment is not paralleled in uranium chemistry. The two isostructural oxides, (μ-O)[An(Cp)3]2 (An = U, Np), allow a comparative study of the magnetic exchange phenomena between the two actinide centres demonstrating an exceedingly strong antiferromagnetic coupling, which is largely independent of the communicated Kramers NpIV (5f3, 4I9/2) or non-Kramers UIV (5f2, 3H4) ions. To design heterobimetallic systems, the uranyl(VI) complexes, [(UVIO2)(THF)(H2L)], supported by the calix[4]pyrrole Schiff base macrocycles, H4LOct and H4LEt, were singly-reduced to uranyl(V) with either of the actinide complexes Np(Cp)3 or U(Cp)3, affording isostructural [(Cp3)AnIVOUVO(THF)(H2L)]. Preliminary investigations of the magnetism of the AnIV-O-UV are reported, although their analysis gave counterintuitive results. Chapter four explores the redox chemistry and molecular and electronic structure of neptunium(III) complexes of the doubly deprotonated trans-calix[2]benzene[2]pyrrole, H2(LAr), macrocycle which has a unique π-bonding potential and conformational flexibility. Interestingly, the reactions with neptunium(IV) chloride yielded mono- and dinuclear neptunium(III) complexes, [(LAr)NpCl] and [(LAr)Np2Cl4(THF)3], with a subsequent elimination of the ligand radical; both complexes adopted η6:κ1:η6:κ1 bis(arene) sandwiched structural motif. In a direct analogy to the redox behaviour occurring in the salt metathesis between Np(Cp)3Cl and KCp, the spontaneous reduction derives from the favourable Np(IV)/Np(III) redox system. The reduction of complex [(LAr)NpCl] with NaK3 in DME produces near-black solutions consistent with [NpII(LAr)(DME)] that in the absence of excess NaK3 gradually convert to the metallated (LAr-H)3- neptunium(III) complex, [K(DME)(LAr-H)NpIII(OMe)]2, featuring the actinide centre bound with a ‘metallocene-type’ geometry provided by the two η5-bound pyrrolides of the ligand. The neptunium(III) compounds were characterized in the solid state by single crystal X-ray diffractometry, ATR(IR) spectroscopy and in a solution by NMR and UV-Vis-NIR spectroscopy.
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Shen, Chengshuo. "Heteroatomic and organometallic helicenes : synthesis and chiroptical properties." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S159.
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Mes travaux de thèse se sont portés sur la synthèse d'hélicènes organométalliques et hétéroatomiques, et se divisent suivant trois axes majeurs. Le premier sujet est l'étude des hélicènes avec un centre métallique redox. Nous avons introduit un motif chimique contenant un atome de fer sur l'hélicène connecté par une liaison C≡C. Dans ce sujet, nous avons étudié les propriétés chiroptiques avec le changement d'état redox du centre métallique. Pour cela, nous avons utilisé des techniques spectroscopiques chiroptiques comme le dichroïsme circulaire vibrationnel, le spectre d'activité optique Raman qui opèrent dans la région infrarouge. Le deuxième sujet est l'étude d'hélicènes avec un centre rédox et un centre photochrome. Nous avons introduit l'hélicène sur un bloc chimique contenant du ruthénium connecté par liaison une C≡C, puis introduit le motif photochrome DTE (dithiényléthène) sur le ruthénium. La molécule contient donc trois parties : un centre chiral, un centre rédox et un centre photochrome. Dans ce sujet, nous avons étudié l'activité d'interrupteur chiroptique provoquée par un stimulus redox et/ou par la lumière. Le troisième sujet est l'étude de platinahélicènes et de borahélicènes qui sont issus de l'incorporation d'un ou deux platinacycles ou cycles azaboroles dans le squelette de l'hélicène. Dans ce sujet, nous avons examiné les propriétés optiques et chiroptiques, et étudié l'influence du nombre de cycles et du nombre d'hétérocycles. Ces produits ont également révélé des propriétés d'émission et de la luminescence polarisée circulairementMy PhD work has focused on the synthesis of organometallic and heteroatomic helicenes and is separated into three subjects. The first subject is the study of helicene with one redox metal center. We have introduced a building block containing an iron atom on the helicene connected by a C≡C bond. In this subject, we have studied the chiroptical properties with the change of the redox state of the metal center. Besides, we have used the techniques of chiroptical spectroscopies such as the vibrational circular dichroism, the Raman optical activity which occur in the infrared region. The second subject is the study of helicenes with one redox center and one photochromic center. We have introduced the helicene on the ruthenium building block, and then introduced a photochromic unit DTE (dithienylethene) on the ruthenium through C≡C bonds. This molecule contains three parts: one chiral center, one redox center and one photochromic center. In this subject, we have studied the redox- and/or light-triggered chiroptical switching activity. The third subject is the study on the platinahelicenes and borahelicenes which show one or two platinacycles or azaborole cycles incorporated in the helicene skeleton. In this subject, we have studied the optical and chiroptical properties, and also studied the influence of the number of cycles and number of the heterocycles. These compounds are also studied in the emission properties and circularly polarized luminescence
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Pearson, Mark. "Organometallic reagents for catalytic cross-coupling." Thesis, University of Oxford, 1992. http://ora.ox.ac.uk/objects/uuid:c5eea9a0-8f0c-46bf-a1ea-28a40b79546d.
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Phosphine complexes of nickel and palladium provide the best catalysts for the homogeneous catalysed carbon-carbon bond forming reaction between an organometallic nucleophile and an organic electrophile. Use of a homochiral ligand on the catalyst can lead to stereoselectivity in the cross-coupling reaction, with high ee's of coupled product being obtained. The processes of selectivity in the transmetalation step of the catalytic cycle have not been elucidated and the initial aim of the project was to study these processes. Initial experiments using organotin derivatives as the organometallic nucleophile highlighted the problems of selectivity and the forcing conditions needed in the attempted transfer of a benzyl group from the tin to the palladium catalyst. The compounds [8- (dimethylamino)-1-naphthyl]methyldiphenyltin (60) and [2-((dimethylamino)methyl) phenyl]methyldiphenyltin (70) were prepared and their reactivity in the palladium catalysed cross-coupling with 2-furoyl chloride, to give 2-benzoylfuran, was investigated. These molecules were found to undergo facilitated transfer of a phenyl group compared to transfer from control molecules. The effect was tested and attributed to the internal nucleophilic attack at the tin atom by the lone pair on the nitrogen atom. The compound [2- ((dimethylamino)methyl)-3-trimethylsilylphenyl]methyldiphenyltin (79) was prepared to test the effects of steric buttressing within the molecule, but was found to be of the same order of magnitude of reactivity as (60) and (70). All three molecules showed a reactivity of at least an order of magnitude greater than control compounds. The effect did not prove applicable to the transfer of a benzyl group or in other coupling reactions. The effect of palladium ligation was tested and the ligand triphenyl arsine found to increase the rate of the coupling reaction. The two facilitating processes were found to work in a co-operative fashion, giving a rate enhancement of ca. one hundredfold over control reactions. The nickel catalysed cross-coupling of α-substituted sp3 hybridised Grignard reagents with allylic esters was attempted, but proved unsuccessful. Stoichiometric reactions with nickel complexes were also found to be unsatisfactory in yielding coupled products. The synthesis of α-substituted diorganozinc reagents was attempted, but furnished only homocoupled products. The reaction of dibenzylzinc with aldehydes was found to proceed in the absence of catalyst, highlighting the reactivity of a benzylzinc moiety.
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Hartnell, Regan David. "The synthesis and investigation of novel n¹-organometallic porphyrins." Thesis, Queensland University of Technology, 2003. https://eprints.qut.edu.au/37151/1/37151_Digitised%20Thesis.pdf.
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Frazier, Joy Faith. "Organo-iridium compounds : synthesis, characterization and reactivity /." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08222009-040309/.
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Choi, Ka Ho. "Synthesis, characterization and properties of luminescent rigid-rod organometallic acetylide materials." HKBU Institutional Repository, 2001. http://repository.hkbu.edu.hk/etd_ra/360.
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Clayton, C. W. "The synthesis and chemistry of some novel trimethylphosphine hydride complexes of iridium." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379909.
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Clark, Robert Andrew. "Studies on novel molecular solids." Thesis, Bangor University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252653.
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Luker, Tim John. "Tandem reactions on a zirconocene template." Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295252.
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Melis, Diana. "Quinoline-triazole half-sandwich iridium(III) complexes: Synthesis, antiplasmodial activity and preliminary transfer hydrogenation studies." Master's thesis, Faculty of Science, 2020. http://hdl.handle.net/11427/32414.
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Malaria is a devastating and pervasive infectious disease and continues to be a major global health issue, with over half the world's population being at risk of transmission. In the absence of a suitable vaccine, efforts to eradicate the disease rely heavily on clinically available drugs. Plasmodium falciparum, the deadliest species of malaria, has however become resistant to most conventional antimalarial treatments, resulting in the worldwide search for new, effective drugs. Amongst other requirements, these drugs should target resistant parasitic strains in an attempt to curb the escalation of the disease. In this regard, the incorporation of a metal into the organic framework of a biologically active compound has become an increasingly popular method of enhancing antiplasmodial activity in the drug-resistant parasite strains. Two series of 7-chloroquinoline-1,2,3-triazole ligands, one with the direct attachment of the triazole to the quinoline and one where the two entities are separated by an aminopropyl linker, were synthesised. Coordination of selected ligands with [IrCl(μ-Cl)(Cp*)]₂ yielded six neutral, cyclometallated and two cationic,N,N-chelated iridium complexes. Computational analysis revealed that metal coordination to the quinoline nitrogen occurs first, forming an unstable kinetic product that, upon heating over time, forms the stable, cyclometallated, thermodynamic product. All of the compounds were fully characterised using an array of spectroscopic (¹H, ¹³C{¹H}, ¹⁹F{¹H}, ³¹P{¹H} NMR and FT-IR spectroscopy) and analytical (mass spectrometry and melting point analysis) techniques. Single crystal X-ray diffraction confirmed the proposed molecular structure and a pseudo-tetrahedral geometry around the metal centre for the cyclometallated and monodentate, quinoline nitrogen-coordinated complexes. The ligand series containing the propyl chain linker displayed superior in vitro antiplasmodial activity against the chloroquine-sensitive NF54 strain of P. falciparum in comparison with the series having thetriazole directly attached to the quinoline moiety. Upon complexation with iridium, the activity of selected ligands is significantly enhanced (0.247< IC₅₀ (μM)< 2.34), with some complexes being over one hundred times more active than their respective ligands. For most of these compounds, their antiplasmodial activity is lower in the chloroquine-resistant K1 strain, however, their calculated RI values suggest that they likely only experience mild cross-resistance, not to the same extent of chloroquine. Selected complexes were tested against the healthy, mammalian Chinese Hamster Ovarian (CHO) cell line and were found not to be cytotoxic. They were also determined to be more selective towards the parasite than healthy cells. An “IC₅₀ speed assay” using the three most active complexes against the chloroquine-sensitive NF54 strain found the two neutral, cyclometallated complexes to be fast-acting compounds which reach their lowest IC₅₀ values within 24 hours, while the active cationic complex was determined to be slow-acting, only reaching its lowest IC₅₀ value after 48 hours. To gain insight into the possible mechanisms of action of these compounds, selected ligands and complexes were tested for their ability to inhibit the formation β-haematin(the synthetic form of haemozoin), sinceone of the mechanisms of 7-chloroquinoline-containing compounds is the inhibition of haemozo information. All five of the tested compounds were found to inhibit β-haematin formation to some extent but were, in general, less effective β-haematin inhibitors than chloroquine itself. Interestingly, the aminopropyl-containing cationic complex which displayed the lowest antiplasmodial activity exhibited far greater β-haematin inhibitory activity (IC₅₀ 9.65 μM) than chloroquine(IC₅₀ 65.3 μM).Finally, three of the most active complexes were evaluated for their ability to facilitate transfer hydrogenation, by reducing β-nicotinamide adenine dinucleotide (NAD+) to NADH in the presence of hydrogen source, sodium formate. Through preliminary qualitative and quantitative cell-free experiments, it was found that the two most active neutral, cyclometallated complexes tested may be capable of acting as transfer hydrogenation catalysts while the active, cationic complex tested did not indicate reduction of NAD+ to NADH over 4 hours.
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Guest, Ruth Winifred. "Synthesis and Reactions of Iron and Ruthenium Dinitrogen Complexes." University of Sydney, 2008. http://hdl.handle.net/2123/3533.
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Doctor of Philosophy (PhD)This thesis is primarily concerned with the synthesis and reactions of iron and ruthenium dinitrogen complexes of tripodal phosphine ligands. Of particular interest is the cationic dinitrogen bridged iron complex [(FeH(PP3))2(μ-N2)]2+ 23, containing the tetradentate ligand P(CH2CH2PMe2)3, PP3 1, and its potential for facilitating the reduction of the bound dinitrogen upon treatment with acid. The synthesis of a selection of novel and known tripodal phosphine and amino phosphine ligands is described. New ligands N(CH2CH2CH2PMe2)3 N3P3 7 and P(CH2CH2CH2PiPr2)3 P3Pi3 11 were synthesised by nucleophilic displacement of bromide from the bromoalkylphosphine and bromoalkylamine precursors with the relevant phosphide. A new method for synthesis of known ligand P(CH2CH2CH2PMe2)3 P3P3 19 by the nucleophilic substitution of its chloroalkylphosphine oxide with dimethylphosphide and subsequent reduction is also reported. The reaction of [(FeH(PP3))2(μ-N2)]2+ 23 with base produced the singly deprotonated mixed valence species [(FeH(PP3))(μ-N2)(Fe(PP3))]+ 37 and subsequently the iron(0) dinuclear species (Fe(PP3))2(μ-N2) 38 and mononuclear complex Fe(N2)(PP3) 44. The 15N labelling of complexes has allowed the 15N NMR spectra of 23, 37 and 44 to be reported along with the observation of a long-range 5JP-P coupling across the bridging dinitrogen of 37. Complexes 23 and 37 were also structurally characterised by X-ray crystallography. The treatment of a variety of iron PP3 1 dinitrogen complexes, including the mononuclear species [(Fe(N2)H(PP3)]+ 22, with acid, or base then acid, did not result in the formation of ammonia from reduction of the complexed dinitrogen. The reactions of FeCl2(PP3) 24 and FeClH(PP3) 25 with ammonia and hydrazine afforded the complexes [FeCl(N2H4)(PP3)] 48, [FeH(N2H4)(PP3)] 47, [FeCl(NH3)(PP3)] 49 and [FeH(NH3)(PP3)] 46. Complexes 47 and 46 are considered potential intermediates in any reduction of the dinitrogen ligand of 23 to ammonia. Complexes 49 and 46 were also formed from the decomposition of the hydrazine complexes 48 and 47. The 15N NMR shifts, derived from both the 15N labelling of complexes and from 1H-15N 2D NMR experiments at natural abundance are reported. In addition, complex 47 was characterised by X-ray crystallography. The novel ligand P(CH2CH2PiPr2)3 PPi3 12 was used in the successful synthesis of [FeCl(PPi3)]+ 51 and [RuCl(PPi3)]+ 56. Reduction of 51 and 56 with potassium graphite under dinitrogen afforded the complexes Fe(N2)(PPi3) 52 and Ru(N2)(PPi3) 57 respectively. This is the first report of a Ru(0) dinitrogen complex. Treatment of 52 and 57 with lutidinium tetrafluoroborate resulted in protonation and oxidation of the metal centre to afford the hydrido complexes [Fe(N2)H(PPi3)]+ 53 and [Ru(N2)H(PPi3)]+ 58 respectively. 15N labelled analogues of 52, 53, 57 and 58 were achieved by exchange reactions with 15N2 gas, allowing for analysis by 15N NMR spectroscopy. Species 52, 57 and 58 have also been structurally characterised by X-ray crystallography. Treatment of 52 with excess acid in THF afforded both 53 and the dihydrogen complex [Fe(H2)H(PPi3)]+ 54. The mechanism of formation of 54 probably involves the C-H activation of the solvent THF. The complex cation [RuCl(P3Pi3)]+ 65 was synthesised using the novel ligand P3Pi3 11. A polymeric iron(II) complex, [Fe2Cl4(N3P3)2]n 66, of the tridentate ligand N3P3 7 was also synthesised. Characterisation of both 65 and 66 by X-ray crystallography is reported. (FeCl)2(μ-Cl)2(μ-Pi2)2 68, an unusual bridged dimer of the known ligand CH2(PiPr2)2 Pi2 67, and iron(II) and iron(0) tetramers of the PP3 1 ligand, namely [Fe4Cl4(PP3)5]4+ 71 and Fe4(PP3)5 72 were also characterised by X-ray crystallography.
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Humphries, Kristina. "Synthesis and reactivity of chiral ferrocene complexes." Thesis, Keele University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265643.
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Peatt, Anna C. (Anna Clare-Doreen) 1976. "New reaction media for organometallic chemistry." Monash University, School of Chemistry, 2003. http://arrow.monash.edu.au/hdl/1959.1/5829.
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Zhang, Fan. "Synthesis of organometallic foldamers and cyclopropene alpha-amino acids." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 211 p, 2006. http://proquest.umi.com/pqdweb?did=1172109511&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Saberi, Stephen Philip. "The synthesis, characterisation and photochemistry of novel organometallic complexes." Thesis, University of Central Lancashire, 1990. http://clok.uclan.ac.uk/20983/.
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Complexation of an organic ligand by a transition metal can radically alter the ligand photochemistry. In order to investigate these effects, we synthesised a series of organometallic complexes with several different modes of ligand-metal bonding. The synthesis of various cyclopentadienyl, arene, diene and enone complexes was attempted. Novel ferrocenyl fulgides, including several methoxy-substituted analogues were synthesised, and have been shown to display E/Z-photoisomerism. In contrast with the report by McVey et al,81 we showed that methoxyferrocene would not Friedel-Crafts acetylate in the 2- or 3-positions using aluminium chloride as the Lewis acid catalyst. Substitution only occurs at the 1'-position, which is thought to be due to deactivation of the methoxy-substituted ring by coordination of the aluminium chloride/acetyl chloride complex by the methoxy group. However, we successfully synthesised the 2- and 3-methoxyacetylferrocenes by replacing aluminium chloride by the more sterically demanding Lewis acid, diethylaluminium chloride. All attempts at using organic fulgides as diene or enone ligands with a series of metals has shown them to be totally unsuitable for this purpose. We succesfully synthesised a wide range of fulgide arene chromium tricarbonyl complexes. Their photochemistry was found to consist of simple E/Z-isomerisation followed by decomposition. However, their thermochemistry proved to be very interesting It was shown that a thermal electrocyclic ring closure reaction could be induced at considerably lower temperatures (i.e: -135°C ) than normal (i.e: -200°C) when a chromium tricarbonyl moiety is attached to the fulgide arene group. A crystal structure of the ring closed product from one of these fulgide chromium complexes shows that the Woodward-Hoffmann rules may have been broken by this metal-mediated ring closure. Efforts were being made to prove that this ring-closure reaction proceeded via a thermally forbidden conrotatory mechanism. Preliminary studies on the use of these chromium tricarbonyl fulgide complexes in the synthesis of hitherto inaccessible fulgides were carried out.
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Tudor, Jonathan Simon. "Synthesis and catalytic activity of organometallic-inorganic composite materials." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339188.
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Aguirre, Etcheverry Paulina Loreto. "The synthesis and characterisation of new homobimetallic organometallic complexes." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496818.
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Hart, Suzanne L. "Synthesis and applications of chiral-at-titanium organometallic compounds." Thesis, University of Warwick, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245941.
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Zeng, Renqiang. "The synthesis, characterization and properties of new organometallic polymers." Master's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/26231.
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We have reviewed recent work on highly branched polymers called dendrimers. Two novel block copolymers consisting of organoruthenium dendritic wedges and linear polyethylene glycol blocks have been prepared. These new block copolymers have been characterized by IR, ¹H and ¹³C NMR, microanalysis, as well as size exclusion chromatography. The SEC results of some very large organoruthenium dendrimers are also discussed. The thermal properties of these block copolymers have been studied by differential scanning calorimetry and thermogravimetric analysis. The morphology of these block copolymers have been studied by transmission electron microscopy. We also describe a preliminary thin film study, resulting from the decomposition of some of the block copolymers. Two ruthenium and platinum complexes containing bulky dendritic phosphine ligands, cis-Pt(RDP)₂Cl₂ and trans,trans,trans-RuCl₂(CO)₂(RDP)₂, have been prepared. These new phosphine complexes have been characterized by IR, ¹H, ¹³C and ³¹P NMR, as well as elemental analysis. We also discuss the potential catalytic application of these dendritic phosphine metal complexes in the hydroformylation reaction.
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Skilbeck, Melanie C. "Synthesis of substituted nitriles and indoxyls using organometallic reagents." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4652/.
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Webb, Samantha Jane. "The synthesis of functionalized polysilanes for microlithographic applications." Thesis, University of Kent, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240671.
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Dolby, P. A. "Synthesis and reactivity of unsaturated triosmium carbonyl clusters." Thesis, University of Liverpool, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233836.
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Kamarudin, R. A. "The synthesis and study of some haxanuclear clusters." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233257.
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Cloete, Jezreel. "Synthesis and applications of functionalized pyridinyl imine complexes of palladium." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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The synthesis and characterization of pyridinyl &alpha-diimine Pd(II) complexes having a functionalized hydrocarbon attached to the imino nitrogen was performed. The catalytic activity of these complexes were then evaluated in the polymerization of ethylene and in the Heck coupling reaction of methyl acrylate with iodobenzene.
Unconjugated &beta
-diimine complexes of palladium were also synthesized and their activities towards ethylene polymerization and the Heck coupling of methyl acrylate and iodobenzene also evaluated and compared to that of the &alpha
-diimine complexes. Three of the &alpha
-diimine complexes synthesized showed activity towards ethylene polymerization, these being the complexes bearing the allyl, styrene and phenol functionalities. &omega
-Carboxylato complexes which were also synthesized showed no activity towards ethylene polymerization.
The polymer produced was found to be high density linear polyethylene with an average PDI of 2.54 with Mn values ranging between 3.42 and 6.90 x 10-5 and Mw values ranging between 6.05 and 17.6 x 10-5.
The complexes bearing the allyl, styrene and phenol functionalities, as well as the &omega
-carboxylato complexes active in the Heck coupling reactions of methyl acrylate with iodobenzene. None of the unconjugated &beta
-diimine complexes prepared showed any activity towards ethylene polymerization even at high Al/Pd ratios. The activity of these complexes towards the Heck arylation reaction was comparable to that of the &alpha
-diimine complexes showing similar activities.
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Buffet, Jean-Charles. "Homochiral metal complexes for biodegradable polymer synthesis." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4618.
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Chapter One introduces the principle of alkoxide and phosphine oxide as ligands for lanthanides and electropositive metals, ligand self-recognition, stereoselective polymerisation of lactide, fixation of CO2 and finally copolymerisation of CO2 and epoxide. Chapter Two shows the synthesis of the proligands rac-HLR (a racemic phosphine oxide-alkoxide, A, where R = tBu, Ph or C6H3-Me-3,5) and explores the resolution into diastereomeric RRR- and SSS-M(LR)3 to afford C3–symmetric M(LR)3 complexes, B (where M = Sc, Lu, Y, In, Bi or La). It also demonstrates that the process is under thermodynamic control and driven by ligand self-recognition via the synthesis of bis(LR) adducts (LR)2MX, C, (where M = Y or In and X = N(SiMe3)2 or OC6H3-tBu2-2,6) and mono(LR) adducts (LR)MX2, D (where M = Al or In and X = N(SiMe3)2, CH2SiMe3 or Me). Finally, it outlines the fixation of CO2 into an indiumamide bond. Chapter Three contains a detailed investigation of the potential of the MIII complexes as initiators for the stereoselective polymerisation of lactide, - caprolactone, glycolide and copolymerisation of lactide and -caprolactone, lactide and glycolide and CO2 and epoxide. Chapter Four investigates the use of rac-HLtBu in the resolution into diastereomeric RR- and SS-M(LtBu)2 complexes, E (where M = Ca, Zn or Sn), and of rac-HLPh into [M(LR)2]2 complexes, F (where M = Mg, Co or Sn and R = Ph or C6H3-Me-3,5) and mono-(LtBu) adducts (LtBu)MgX, G (X = N(SiMe3)2 or OC6H3-tBu2-2,6). It also describes the synthesis of protonated MII complexes (HLR)MCl2, H (where M = Mg, Zn or Sn and R = tBu or Ph). Finally, it details the polymerisation of lactide and its copolymerisation with glycolide using MII complexes as initiators. Chapter Five gives full experimental details and analytical data for the herein described novel compounds.
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Callahan, Ryan Patrick. "The synthesis of perfluorinated compounds by direct fluorination organometallic compounds and carboranes /." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3036160.
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Sharp, William Brett. "Synthesis and ligand reactivity of group 6 organometallic nitrosyl complexes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ61173.pdf.
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