Dissertations / Theses: 'Organic metal complexes'

1

Jones, P. "Studies of chiral metal complexes." Thesis, Bucks New University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373593.

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2

Green, G. "Transition metal oxo-complexes as organic oxidants." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37711.

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3

Andernach, Rolf. "Conjugated polymer-metal complexes for organic electronics." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/43382.

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Organometallic complexes play a crucial role in Organic Electronics and due to their interesting optoelectronic properties they have been widely applied in organic light-emitting diodes and organophotovoltaic devices. Organometallic complexes are often used in the form of small molecules and their exact orientation in the bulk material can have a major effect on device performance. In this work, different approaches of covalently incorporating metal-porphyrin complexes into polymers were explored with the aim of producing homogeneous donor-acceptor type polymers which allow for the elimination of phase separation effects within the active material of the respective devices. A set of design rules was developed for the creation of porphyrin-polymer complexes and their application as host-guest systems in the triplet-sensitisation of semi-conducting polymers was studied, determining the optimal functional groups as well as matching absorption and emission properties. To this end, a synthesis pathway was developed that enabled the creation of metal porphyrins as well as their specific functionalisation for use in different co-polymerisation reactions. Platinum (II), palladium (II) and zinc (II) porphyrins were synthesised and successfully incorporated into a series of semi-conducting polymers: regiorandom and regioregular poly(3-hexylthiophene) (P3HT), poly(bis(decylthiophene)phenylene) (TTP) and poly(para-phenylenevinylene) (PPV). Successful co-polymerisation was reported for all polymers and the electronic interaction between the polymer hosts and porphyrin guests was analysed. The successful creation of triplet-sensitised polymers was shown and the full triplet formation pathway was mapped by spectroscopic means, creating a novel tool for the generation and analysis of polymer triplet excitons. Finally, computational methods were used for the accurate description of polymer triplet excited states and their usefulness in the prediction of excited state properties was shown. Polymer models were designed, computed and compared to experimental data and the use of computational methods as a widely applicable and precise tool for determining polymer excited states was discussed, further substantiating the design rules developed throughout this work.

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4

Paver, Michael A. "Novel p-block metal anion complexes." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/271941.

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5

Hartstock, Frederick W. "Activation of organic molecules by transition metal complexes." Thesis, University of Ottawa (Canada), 1987. http://hdl.handle.net/10393/5306.

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6

Warner, P. "Asymmetric synthesis via transition metal acyl complexes." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355823.

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7

Wilkes, Stephen Brinley. "Studies on novel redox-active metal complexes." Thesis, Bangor University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359336.

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8

Rowe, Kathryn Elizabeth. "Mesomorphic 2,2'-bipyridines and their metal complexes." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265568.

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9

Quelch, Geoffrey E. "Theoretical studies of some transition metal complexes." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329083.

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10

Worayingyong, Attera O. "Metal complexes as catalysts for stereoselective synthesis." Thesis, University of Aberdeen, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294145.

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Metal complexes have been used as catalysts for stereoselective syntheses in CC bond formation reactions, namely, alkyl- and allyl- additions to aldehydes. The enantiomeric alkylations involved reactions between Et₂Zn and arylaldehydes in the presence of chiral templates, e.g. zinc-, titanium- and boron-complexes of (S)-(-)-2-amino-3-(p-hydroxyphenyl)-1,1-diphenylpropanol. The reaction has been proved to be catalytic, using 3-5 mol% of the chiral ligand in the addition of Et₂Zn to p-tolualdehyde. Study of the substituent effects in arylaldehydes showed that p-tolualdehyde leads to the highest optical yield (83%ee) when a chiral Schiff base-zinc complex is formed. The in-situ produced chiral templates for the alkylations were studied by two different methods. Firstly, the alkyl metal itself; i.e. Et₂Zn, acts as the metal key atom. Secondly, other metal compounds; i.e. BH₃.THF and Ti(OPrⁱ)₄ formed chiral auxiliary complexes for the additions of Et₂Zn to arylaldehyde. The highest optical yield for 1-p-tolylpropanol [ca. 80%ee (S)] was obtained using the zinc- and boron-complexes. The chiral amino alcohol was also deposited onto silica gel to act as a heterogeneous catalyst. The asymmetric ethylations of p-tolualdehyde using the silica gel supported ligand have been tested with zinc-, titanium- and boron-complexes. Diethylzinc alone provides the best selectivity (53%ee), the values for the boron and the titanium systems are 16 and < 1%ee, respectively. On subsequent use of the solid catalyst, the optical yields fall off. Allylic additions of Bu₃SnCH₂CH=CH₂ to arylaldehydes have been examined in the presence of the chiral amino alcohol and titanium compounds. The optimum result was found to occur when TiCl₄ was reacted with the amino alcohol prior to the simultaneous addition of the reacting materials. However, the chiral allylic alcohol was obtained in low optical yield (31%ee).

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11

Sheridan, J. B. "The reactions of transition metal hydrocarbon complexes." Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356238.

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12

Lin, Bing. "Organometallic chemistry of transition metal polyyne complexes." Thesis, University of Cambridge, 1993. https://www.repository.cam.ac.uk/handle/1810/272565.

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13

Cheung, William M. L. (William Man Lung). "Artificial phosphodiesterases : dinuclear metal complexes with bridging hydroxides." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23875.

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The reactivities of two dinuclear metals complexes with bridging hydroxides for hydrolyzing phosphrite diesters have been examined.
The second-order rate constants ($ rm k sp prime sb{hyd}/M sp{-1} s sp{-1}$) for the hydroxidecatalysed hydrolysis of bridging aryl methyl phosphates in di-$ mu$-hydroxodinuclear cobalt(III) complex ($ rm Co sb2( lbrack 9 rbrack aneN sb3) sb2(OH) sb2(OP(O)(OMe)(OAr) rbrack sp{3+}$ ( (9) aneN$ sb3$ = 1,4,7-triazacyclononane) and the corresponding free aryl methyl phosphates (25$ sp circ$C and 0.1 M ionic strength) obey the following Bronsted equations: eqalign{ rm log k sp prime sb{hyd} (free diester) = -0.70 pK sb{ rm a}-0.66 & quad rm(R = 0.996) cr rm log k sp prime sb{hyd} (bridging diester) = -1.40 pK sb{ rm a} + 14.4 & quad rm (R = 0.999) cr} hese linear free energy relationships suggest that the di-$ mu$-hydroxodinuclear cobalt(III) complex, irrespective of the leaving groups hydrolyzes the bridging phosphate diesters by the same mechanism. They also indicate that the complex provides greater rate-acceleration for hydrolyzing phosphate diesters with good leaving groups than with poor ones.
La(III) cooperates with hydroxide in hydrolyzing bis(4-nitrophenyl) phosphate (BNPP). The close agreement between the titration data and the pH-rate profile indicates that the active core of the catalyst is a dinuclear La(III) complex bridged by five hydroxide ions La$ rm sb2(OH) sb5 sp+.$ The mechanism proposed for $ rm La sb2(OH) sb5 sp+$-promoted hydrolysis of BNPP involves double Lewis acid activation and intramolecular nucleophilic catalysis of the bridging hydroxide.

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14

Young, Mary Jane. "Phosphate diester cleavage mediated by transition metal complexes." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40473.

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Two independent studies have been developed in this thesis. In the first study, the reactivities of metal-alkoxide and metal-hydroxide nucleophiles are compared for cleaving phosphate diesters. In the second study, the reactivity of a dinuclear metal complex is compared to a mononuclear metal complex for hydrolyzing RNA.
Copper(II) complexes of bis(2-pyridylmethyl)amine (Cu(II)bpa), N-(2-hydroxyethyl)bis(2-pyridylmethyl)amine (Cu(II)hebpa) and N-(3-hydroxypropyl)bis(2-pyridylmethyl)amine (Cu(II)hpbpa) have been synthesized and their reactivities and mechanisms for cleaving bis(2,4-dinitrophenyl) phosphate (BDNPP) have been investigated. Cu(II)hpbpa is observed to be the most reactive (k = 7.2 $ times$ 10$ sp{-1}$ M$ sp{-1}$ s$ sp{-1}$ at 25$ sp circ$C, pH 8.8) for cleaving BDNPP followed by Cu(II)bpa (k = 2.0 $ times$ 10$ sp{-2}$ M$ sp{-1}$ s$ sp{-1}$) and Cu(II)hebpa (k = 2.0 $ times$ 10$ sp{-2}$ s$ sp{-1}$). HPLC product analyses indicated that Cu(II)hpbpa cleaves BDNPP mostly through transesterification while the complexes Cu(II)bpa and Cu(II)hebpa cleave BDNPP predominantly by hydrolysis. The differences in the mechanisms and the reactivities are explained in terms of the differences in the structures of the three copper(II) complexes.
Copper(II) complexes of 1,8-bis(1,4,7-triazacyclononyl-N-methyl)naphthalene (tntn), 1,4,7-triazacyclononane (tacn), and N-benzyl-1,4,7-triazacyclononane (btacn) have been prepared and their reactivities compared for cleaving RNA. The novel dinuclear copper(II) complex, Cu(II)$ sb2$tntn, is observed to be 200-500 fold faster per metal center than the mononuclear copper(II)complexes, Cu(II)tacn and Cu(II)btacn, for cleaving a diribonucleotide, ApA, and its cyclic phosphate intermediate, $2 sp prime3 sp prime$-cAMP. Cu(II)$ sb2$tntn (2.0 mM) reduces the half life of ApA (0.05 mM) to 50 minutes (pH 6, 50$ sp circ$C); this represents a rate acceleration of approximately 10$ sp5$ fold over the background hydroxide rate. The half life of $2 sp prime3 sp prime$-cAMP (0.05 mM) is decreased to 4 minutes in the presence of Cu(II)$ sb2$tntn (2.0 mM, pH 6, 25$ sp circ$C); this represents a rate acceleration of about 10$ sp8$ fold over the background hydroxide rate.

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15

Zissimos, Andreas M. "Structural studies of model compounds of salicylaldoxime metal extractants and their complexes, and of related metal complexes of dioxime systems." Thesis, London Metropolitan University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323383.

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16

Herring, A. M. "New transition metal complexes containing functionalised phosphine ligands." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383967.

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17

Gilbert, M. "Carbon-carbon coupling reactions of organotransition metal complexes." Thesis, University of Bristol, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235314.

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18

Biddulph, M. A. "Reactivity of some paramagnetic low-valent metal complexes." Thesis, Kingston University, 1985. http://eprints.kingston.ac.uk/20495/.

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19

Thompson, Alexander Martin Williams Cargill. "Transition metal-terpyridine complexes as supramolecular building blocks." Thesis, University of Cambridge, 1993. https://www.repository.cam.ac.uk/handle/1810/272557.

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20

Cairns, Gareth Alan. "Novel aspects of alkyne substituted transition metal complexes." Thesis, University of Bath, 1998. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242813.

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21

Han, Shou. "Magnetism in multiferroics and low dimensional metal-organic complexes." Thesis, Queen Mary, University of London, 2016. http://qmro.qmul.ac.uk/xmlui/handle/123456789/23198.

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Multiferroics and magnetic metal-organic complexes are candidates for sophisticated applications in the future. In thisthesis, the magnetism in BiFeO3 (a multiferroic material with an incommensurate spin cycloidal structure), copper guanidiniam formate (a multiferroic metal-organic complex with a one-dimensional magnetic structure) and CP -RE-COT (a series of \zero-dimensional" single molecule magnets) are discussed. A radio-frequency plasma sputtering thin lm deposition system and a ferroelectric characterisation system were developed for the study of BiFeO3 epitaxial thin lms. A large leakage current was observed in BiFeO3 thin lms, which hindered the investigations on the ferroelectric properties and magnetoelectric coupling in them. An evidence of the spin cycloid in a BiFeO3 thin lm was observed by grazing-incidence small angle neutron scattering. The magnetism of a multiferroic metal-organic complex with a one-dimensional magnetic chain, [C(NH2)3][Cu(HCOO)3], was studied by magnetometry and muon spin spectroscopy. A spin-canted antiferromagnetic order and critical phenomenon in this material were investigated. It was shown that this material possessed an 3D Heisenberg long-range order below 4.6K. The one-dimensional magnetic chain was also studied by muon spin spectroscopy. The correlation length was measured with a eld dependence of H 1. Magnetisation relaxations of a series of single molecule magnets CP -RE-COT (COT = C8H8- CP = C5Me, which show "zero-dimensional" magnetism, were studied using an AC magnetometer and muon spin spectroscopy. Three possible relaxation pathways, including a quantum tunnelling process and two Orbach relaxation processes, were suggested by the relaxation behaviour. The suppression of the quantum tunnelling effect resulting from the entanglement of the ground states, which probably arises from the exchange interactions in CP -RE-COT, was also observed with a 1000 Oe applied magnetic eld. Data that were consistent with long-range magnetic ordering was observed in CP -Dy-COT, which would be the fi rst ever report of long-range magnetic order in a single ion magnet.

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22

Hamdy, Louise. "Developing new hydrogen bonded alkaline earth metal-organic complexes." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.675739.

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This investigation addresses the understudied area of the research and development of hydrogen bonded metal-organic complexes featuring the alkaline earth metals magnesium and calcium. This work presents the crystal structures and thermal behaviour of a series of metal-organic and organic crystalline complexes synthesised from metal salts and pyridine carboxylic, dicarboxylic acid and chloranilic acid ligands, characterised primarily by X-ray diffraction. Chapter 1 introduces crystal engineering, intermolecular interactions, and functional crystalline materials, followed by a literature review addressing metal-organic frameworks (MOFs), hydrogen bonded metal-organic complexes, magnesium MOFs and alkaline earth metal complexes synthesised from pyridine carboxylic, dicarboxylic and tricarboxylic acid and chloranilic acid. Chapter 2 outlines the theory of the techniques used to analyse the synthesised materials, focusing on single crystal X-ray diffraction, followed by Chapter 3 which documents the sample preparation and the experimental details. Chapter 4 describes the crystal structures of fourteen coordination complexes synthesised from magnesium and calcium salts and the three isomers of pyridine carboxylic acid. This work was carried out in order to identify structural trends such as the most common coordination geometries of the metal centres, the ways in which the ligands coordinate and any recurring hydrogen bonding motifs. Chapter 5 discusses attempts to synthesise an alkaline earth metal analogue of a metal-containing ‘metalloligand’ of the formula M(C7H4NO4)2(H2O)2, in which the metal (M) is N,O-chelated by pyridine-2-carboxylate-4-carboxylic acid, and the subsequent combination of these materials with the diamines o-tolidine and m-xylylenediamine. This chapter also reports the structure of a magnesium coordination complex resulting from a hydrothermal reaction, and the subsequent transformation of this complex to a new crystal structure which contains the doubly deprotonated magnesium analogue of the originally targeted ‘metalloligand’. Chapter 6 describes the crystal structures of three complexes synthesised from pyridine carboxylic acids and chloranilic acid, and the complex resulting from the combination of one of these organic ‘supramolecular ligands’ with a copper salt. Finally, two new calcium-chloranilate coordination polymers are reported, one of which has an interesting anionic 3D structure.

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23

Doherty, Cheryl Louise. "Structural studies on hydrogen-bonded and metal-organic complexes." Thesis, University of Bath, 2005. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425805.

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24

Bell, Steven Ernest John. "Transient electronic and resonance Raman spectroscopy of some photoexcited transition metal and metal-carbene complexes." Thesis, Queen's University Belfast, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317048.

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25

Litster, Stephen Anthony. "Studies in the structural chemistry of transition metal complexes with agostic and metal-hydrogen interactions." Thesis, University of Salford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305867.

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26

Quereshi, K. B. "Studies of fluxional characteristics of organic ligand complexes." Thesis, University of Essex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378240.

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27

Das, Sanjit. "Enhanced Structural Support of Metal Sites as Nodes in Metal-Organic Frameworks Compared to Metal Complexes." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1736.

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Metal-organic frameworks are a new class of crystalline, porous solid-state materials with metal ions periodically linked by organic linkers. This gives rise to one-, two- or three-dimensional structures. Here, we compare the stability of similar metal sites toward external ligand (solvent) induced disruption of the coordination environment in metal complexes and in metal-organic frameworks. Our experimental results show that a metal site as node of a metal-organic framework retains much higher stability compared to a similar metal site in a metal complex.

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28

Partridge, Martin Graham. "Activation and coordination of organic ligands by cyclopentadienyl metal complexes." Thesis, University of York, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304072.

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29

Bellamy, Dena. "Intermolecular interactions in transition metal complexes and analogous organic species." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389380.

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30

Khandelwal, Amit Harikant. "Lithium, sodium and lanthanide metal inorganic and organic salt complexes." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272664.

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31

Cragg-Hine, Ian. "Early main group metal complexes of multi-functional organic molecules." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/271932.

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32

O'Connor, Alice. "High pressure studies of metal-organic frameworks and coordination complexes." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/40333/.

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High pressure X-ray crystallography is an effective tool for studying the behaviour of systems in the solid state. It is becoming an increasingly popular technique and offers a way to determine and monitor the behaviour of systems, which in some cases is necessary in order for those particular materials to be used in real-world applications. This thesis explores the use of high pressure X-ray crystallography to understand the behaviour of systems such as metal-organic frameworks (Chapters 4and 5) and the coordination complexes, [1,4-C6H4{PPh2(AuCl)}2](Chapter 6) and chloro(4-ethoxycarbonyl-6-phenyl-2,2′-bipyridyl)platinum (Chapter 7). It also describes hydrostatic limit determinations carried out on 4:1 MeOH/EtOH with additional additives such as silicon grease and/or crystals of [PdCl2([9]aneS2O)] to see how the hydrostatic limit might be manipulated by the use of these additives. It has been possible to determine the hydrostatic limit of a possible pressure-transmitting medium, namely RS3000, which showed an increased pressure limit when compared to the hydrostatic limits for other similar media. This thesis therefore covers a wide range of studieshighlighting some of the diversity that this fieldoffers. To betterunderstand the behaviour of the systems studied, several ancillary techniques have been employed including Hirshfeld surface analysis, Raman spectroscopy, UV/visible spectroscopy and theoretical calculations. In all cases these techniques provided useful information which complemented the results of the high pressure X-ray crystallographic studies.

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33

Hankin, Danielle Maxine. "The chemistry of sulfenamido and selenamido metal and metalloid complexes." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339233.

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34

Cupertino, D. C. "Reactions of highly functionalised alkenes with some transition metal complexes." Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370840.

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35

Miles, A. D. "Synthetic and structural aspects of some heteronuclear metal cluster complexes." Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356226.

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36

Liu, Haichuan. "Reactions in gaseous metal-organic complexes induced by the photoexcitation of the metal chromaphores /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202004%20LIU.

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37

Ansari, Nasrin. "Coordination properties of aminophosphine with first row transition metal nitrosyl complexes." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/6862.

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The synthesis of the new thermolabile ironnitrosylhydride complex FeH(NO)(CO)(dppf) is reported. (dppf = 1,1$\sp\prime$-bisdiphenyl phosphino-ferrocene). The facile decomposition of FeH(NO)(CO)(dppf) is interpreted in terms of a homolysis of the Fe-H bond and of a nitrosyl transfer reaction. The synthesis of the structurally characterized iron complex Fe(O=PPh$\sb2$(2-Py))$\sb3\sp2\sp+\cdot$2BF$\sb4\sp-$, by the reaction of Fe(NO)$\sb2$(THF)$\sb2\sp+$ with PPh$\sb2$(2-Py) is described. The proposed mechanism for the formation of Fe(O=PPh$\sb2$(2-Py))$\sb3\sp2\sp+\cdot$2BF$\sb4\sp-$ involves a combination of disproportionation and oxygen transfer reactions. This dipositive iron complex is the first example of a first row transition metal chelated by the oxide of diphenyl(2-pyridyl)phosphines. The synthesis and the reactivity of the cobaltdinitrosyl monometallic Co(NO$\sb2$(PPh$\sb2(2$-Py))$\sb2\sp+\cdot$BF$\sb4\sp-$, Co(NO)$\sb2$(Py)$\sb2\sp+\cdot$BF$\sb4\sp-$, Co(NO)$\sb2$(Py)$\sb2\sp+\cdot$BPh$\sb4\sp-$ and bimetallic Co$\sb2$(NO)$\sb3$(PPh$\sb2$(2-Py))$\sb2\sp+$ -BPh$\sb4\sp-$ complexes are reported. The single crystal X-ray diffraction study of Co(NO)$\sb2$(PPh$\sb2$(2-Py))$\sb2\sp+$BF$\sb4\sp-$ shows that the aminophosphine ligands are co-ordinated through their P-donor sites. In solution, Co(NO)$\sb2$(Py)$\sb2\sp+$BF$\sb4\sp-$ was stable whereas, Co(NO)$\sb2$(Py)$\sb2\sp+$BPh$\sb4\sp-$ decomposed rapidly. The structural study of Co(NO)$\sb2$(Py)$\sb2\sp+$BF$\sb4\sp-$ has led to the proposal of a new theoretical model in which the non-bonded repulsions between the NO and L ligands of the M(NO)(L) moieties provide the most influential factor for fixing the value of the (O)N-M-N(O) angle. The structurally characterized Co$\sb2$(NO)$\sb3$(PPh$\sb2$(2-Py))$\sb2\sp+$ -BPh$\sb4\sp-$ complex is the first example of a bimetallic containing two metal-metal bonded first row transition metals with diphenyl(2-pyridyl)phosphine as a bridging ligand. It is also the first example of a Co$\sb2$(NO)$\sb3\sp+$ bimetallic core stabilized by two diphenyl(2-pyridyl)phosphine ligands coordinated by the P and N donor sites of the ligands arranged in a head-to-head fashion.

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38

Jolly, B. S. "Sterically hindered organic complexes of the heavier group 14 elements." Thesis, University of Sussex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383558.

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39

Källström, Klas. "Catalytic Asymmetric Ketone and Alkene Reductions Using Transition Metal Complexes." Doctoral thesis, Uppsala University, Department of Chemistry, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6839.

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This thesis contains seven papers dealing with iridium and ruthenium based catalytic asymmetric reductions, either of ketones into chiral alcohols, or olefins into chiral alkanes. The first part of the thesis describes how we have designed and evaluated new bicyclic ligands containing either N,S or N,N chelating atoms. The ligands have been evaluated in the asymmetric Ir-catalyzed transfer hydrogenation of acetophenone. The complexes evaluated induced good enentioselectivity of the product. Moreover we have also utilized a commercially available chiral diamine (QCD-amine) as a ligand in the Ru-catalyzed hydrogenation of prochiral ketones, with excellent enantioselectivity for some of the substrates used. As part of this work we investigated, both theoretically and experimentally, the mechanism of this hydrogenation. Based on these results we have proposed a new reaction mechanism for this type of hydrogenations which involves active participation of the solvent in the catalytic cycle. The last part of the thesis describes the design, synthesis and evaluation of N,P and N₂C-carbene,N ligands for the Ir-catalyzed hydrogenation of carbon-carbon double bonds. The selectivities obtained in these investigations are among the best reported so far for a broad variation of substrates. A selectivity model for this hydrogenation has been derived and used in the rationalization of the results. As a part of this work we have synthesized and evaluated a new class of substrates, vinyl silanes, and showed that the scope of the hydrogenation reaction can be expanded to this new substrate class.

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40

Alsindi, Wassim Zuhair. "Solvent based switching of photophysical properties of transition metal complexes." Thesis, University of Nottingham, 2007. http://eprints.nottingham.ac.uk/13786/.

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The work presented in this Thesis describes the modular design and spectroscopic study of polynuclear systems based on ruthenium (II) and rhenium (I) complexes. A combination of UV/vis, luminescence and TRIR spectroscopies, electrochemistry, spectroelectrochemistry and conformational analysis have been employed to understand the electronic structure of the ground and excited states of these compounds. Chapter I gives an introductory background to this Thesis. An overview of transition metal photophysics and excited states, and the typical spectroscopic and electrochemical techniques used in their study is presented. Previous studies of the ground and excited state properties of the complexes [Ru(bpy)3]2+ and [ReCl(CO)3bpy)] which are used as supramolecular building blocks in this Thesis are presented and a number of relevant studies of supramolecular systems are described. Chapter 2 contains a study extending the known family of [Ru(CN)4(NN)]2- complexes and describes their unique advantages over [Ru(bpy)3]2+. The results obtained are discussed alongside previous studies. This completes the introduction of the molecular building blocks used in Chapters 3 and 4. Chapter 3 details a study of through-space PEnT in bimetallic systems constructed from the complexes introduced in Chapters I and 2, bridged by a saturated alkyl linker between bpy ligands on either metal. This Chapter demonstrates the solvent-switchable nature of the direction and gradient of PEnT, using ps-TRIR spectroscopy to directly probe these processes in real time. Chapter 4 describes a study of bimetallic systems bridged by conjugated the ligand 2,2'- bipyrimidine. Monometallic, homobimetallic and heterobimetallic systems are studied and questions arising from limitations of previous studies are addressed. In particular ps-TRIR spectroscopy gives new insight into the numerous ultrafast processes occurring. Chapter 5 summarises the achievements of this Thesis and suggests promising directions for extending this work in the future. Chapter 6 describes the experimental and theoretical techniques used in this Thesis.

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41

Rooney, Denise. "Time-resolved raman spectroscopy and photolysis of transition metal carbene complexes." Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334489.

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42

Marsden, C. "The synthesis and reactivity of di- and polynuclear mixed metal complexes." Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356224.

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43

Ying, Tsang Min. "Multifunctional N,O-type carborane-based materials: from molecular complexes to three dimensional metal-organic frameworks." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/305240.

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1) Por un lado se describe la síntesis de derivados del orto-, meta- y/o para-carborano mono- and bis-funcionalizados con grupos alcohol metil piridinas, con énfasis en la naturaleza quiral de dichasmoléculas y las estructurassupramoleculares en el estadosólido. El análisis de las estructurasmoleculares y supramoleculares de los derivados monosubstituidos racémicos y enantioméricamente puros obtenidos se han comparado con derivados relacionados anteriormente publicados. Esto ha permitido encontrar una correlación entre los ángulos de torsión OCCN de las moléculas y quiralidad de las hélices supramoleculares que se observan en dichasestructuras. En el caso de los derivados bis-funcionalizados, los resultados muestran que las estructuras supramoleculares estándominadas por interacciones de hidrógeno OH…N y/o OH…O. El análisis de dichasestructuras ha revelado una posible preferencia por el autoensamblado homoquiral frente al heteroquiral. 2) Por otrolado se describe la química de coordinación de los derivados orto- y meta-carborano mono-funcionalizados con grupos alcohol metil piridinas. Así, se han preparado y caracterizado complejos dinucleares quirales de Fe(III) asimétricos. Se han estudiado propiedades magnéticas, quirópticas y en óptica no líneal. En este apartado se describe una sorprendentere solución expontánea por precipitación. El bloquefinaliza con los primerosejemplos de complejos de Cu(I) de los ligandos monosubstituidos, todo sellos luminiscentes en estadosólido. 3) En otra sección de la tesis se han recogidotodos los resultados referentes a la química de coordinación de los derivados orto- y meta-carborano bis-funcionalizados con grupos alcohol metil 2-piridina. Por un lado se describe la síntesis, caracterización y propiedades catalíticas de una serie de complejos NBN pincer de paladio. Por otro, se describen los primeros ejemplos de complejos dinucleares de Fe(III) con los ligandos bis-funcionalizados. 4) En el últimoapartado se describentodos los resultados encontrados en la química de coordinación de los derivados orto- y meta-carborano bis-funcionalizados con grupos alcohol metil 3- y 4-piridinas. La rica capacidad de coordinación de estos nuevosligandos bis-funcionalizados ha permitido preparar complejos moleculares de Pd, polímeros de coordinación de Zn y una novedos a familia de Metal Organic Frameworks (MOFs) en los que se combinan los ligandos bis-funcionalizados con acidos carboxílicosorgánicos y Zn o Co. En este último apartado se describen las propiedades que los ligandos bis-funcionalizados aportan a los MOFs, entre las que se encuentra una mayor estabilidad en agua.
1) The first section describes the synthesis and characterization of the mono- and di-substituted carborane-based pyridylalcohol derivatives with ortho-, meta- and/or para-carborane, with emphasis onthe chiral nature and supramolecular structures of such molecules in the solid state.The molecular and supramolecular structures for the racemic and enantiopure monosubstituted derivatives have been compared with those previously reported. It has been found a possible correlation between the OCCN torsion angles of the molecules and the chirality of the supramolecular helices found in the structures. In the case of the di-substituted derivatives, it was found that the supramolecular structures are dominated by intermolecular OH…N and/or OH…O hydrogen bonds. The analysis of the structures revealed a preference for homochiral self-assembly over heterochiral. 2) Then it is described the coordination chemistry of monosubstituted methylalcohol pyridine ortho- and meta-carborane derivatives. Thus, chiral and unsymmetric Fe (III) complexes have been prepared and characterized. It has been studied their magnetic, chiroptical and non lineal optical properties. It is also described a surprising spontaneous resolution on precipitation. This part is then ended with the first examples of Cu (I) complexes incorporating the monosubstituted ligands and their luminescence properties in the solid state. 3) In the following section of the thesis it is summarized all results dealing with the coordination chemistry of disubstituted methylalcohol 2-pyridine ortho- and meta-carborane derivatives. On one hand it is described the synthesis, characterization and catalytic properties of a series of NBN palladium pincer complexes. On another hand, it is described the first examples of dinuclear Fe (III) complexes with such disubstituted ligands. 4) In the last part it is described all results found on the coordination chemistry of disubstituted ortho- and meta-carborane derivatives with 3- and 4-pyridyl alcohol groups. The rich coordination ability of these new di-substituted ligands has allowed the preparation of molecular Pd complexes, Zn coordination polymers and a novel family of Metal Organic Frameworks (MOFs). The latter being a combination of disubstituted ligands, organic polycarboxylic acids and Zn or Co. In this last part, it is described the properties that the disubstituted ligands transfer to the MOFs, such as for example, water stability.

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Parameswaran, Anupama. "Magnetic properties of Mn, Ni and Fe based metal-organic complexes." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-65594.

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This dissertation presents the investigation of magnetic exchange and anisotropy in novel metal-organic complexes containing minimum number of magnetic ions. Such complexes can serve as a model system to understand the exciting magnetic phenomena in such class of materials and also can put forward as candidates for the so called molecular nanomagnets. A direct assessment of the effective magnetic moment and the effective interaction between the metal ions in the complex can be done using magnetization measurements. Here the magnetization studies are performed as a function of temperature and field using a SQUID magnetometer. Yet another powerful tool to characterize and determine the spin levels, the ESR spectroscopic methods, has also been exploited. The study of the dynamical properties of this class of materials was relevant to understand the relaxation mechanism in the low temperatures. For this a new ac susceptometer has been built in house which was another main objective of this dissertation work. The design, fabrication, calibration and automation done on this device is presented in this thesis. The device has been tested using the known molecular magnet Mn12 acetate, and the antiferromagnet Dy2PdSi3. The present work is mainly focused on the magnetic properties of Mn, Ni and Fe based organometallic complexes. The studied Mn dimer with different acceptor and donor ligands exhibit the fine tuning of the electron density at the core of molecular complex by variation in ligands. This in turn shows that the change in peripheral ligands can control the magnetism of the molecule. The influence of the change in Ni-S-Ni bond angle in the magnetic exchange interaction is studied in a Ni(2) dimer and a Ni(2) trimer complex. The Ni dimer complex shows a ferromagnetic interaction (J = -42K) whereas trimer shows an antiferromagnetic interaction (J = 140K). Another Ni based complex bridged via phosphorous has been studied which shows the existence of glassy nature at low temperature. Also a polymeric chain compound based on Fe is studied and presented. All these phosphorous or sulphur bridged complexes are novel materials and these are the first data on these complexes.

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Stengel, Ilona [Verfasser]. "Transition metal complexes and ligand design for organic optoelectronics / Ilona Stengel." Ulm : Universität Ulm. Fakultät für Naturwissenschaften, 2012. http://d-nb.info/1020449322/34.

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46

Davidson, James E. "Modelling and crystallographic studies of organic surface modifiers and metal complexes." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/13575.

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Molecular modelling and crystallographic techniques have been applied to the study of organic molecules used as friction modifiers and metal salt transport reagents. The accuracy of several empirical force fields has been evaluated by calculating low energy conformations of 3-(4-methylbenzoyl) propionic acid and tri acetyl glycerol. These were compared with the crystal structures of related molecules obtained from the Cambridge Structural Database, which contained either the 4-keto-carboxylate moiety or were tri esters of glycerol. Further validation has been carried out by comparing the force field predicted low energy conformations of propionic acid and ethylene glycol with the results of ab initio calculations either obtained from the literature or performed in house. Liquid phase molecular dynamics calculations have been carried out under conditions of constant volume and temperature and of constant temperature and pressure in order to investigate structure – activity relationship in films of physisorbed friction modifiers based on fatty esters of glycerol. We are able to make proposals about how the varying efficacy of mono, di and tri esters of glycerol arises from their structure. The crystal structures of novel complexes of model extractants for salts of base metals have been determined and analysed. These complexes fall into one of four classes: 1) Complexes containing salicylaldoxime ligands; 2) Complexes based on hexadentate tris-salicylaldimine ligands; 3) Complexes based on bipodal hexadentate ligands salicylaldimine ligands; 4) Complexes based on coordination of two tridentate salicylaldimine ligands. For classes 3) and 4) we have investigated the possibility of isomerism using the results of our structure determination and structures obtained from the Cambridge Structural Database. We have also investigated the possibility of a combined molecular dynamics/mechanics approach to asses the efficiency of phase transfer for this type of complex.

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47

Saleem, al-Shaqri Layla Mohammed. "Kinetic studies of inorganic and organic peroxo complexes /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p3099628.

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48

Martin, Jeff. "The synthesis and characterisation of novel ferrocene ligands and their metal complexes." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313662.

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49

Broughton, Simon. "Progress toward a catalytic alkenation using transition metal alkylidene and oxo complexes." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251978.

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50

Chaudhary, Soraya Shezana. "Synthesis of some nitrogen-donor macrocycles and their complexes with metal ions." Thesis, London Metropolitan University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287567.

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Dissertations / Theses on the topic 'Organic metal complexes'

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