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1

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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2

Shan, Hui. "New late transition metal oxo and hydrazido complexes /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9924922.

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3

Cecchini, Chiara. "Late Transition Metal-Oxo complexes: Synthesis, and Biorelevant Reactivity." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11249/.

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High-valent terminal metal-oxygen adducts are supposed to be potent oxidising intermediates in enzymatic catalyses. In contrast to those from groups 6-8, oxidants that contain late transition metals (Co, Ni, Cu) are poorly understood. Because of their high reactivity, only a few examples of these compounds have been observed. The aim of this project was to investigate the reactivity of high-valent Ni(III) complexes, containing a monodentate oxygen-donor ligands, in hydrogen atom abstraction (HAA) and oxygen atom transfer (OAT) reactions which are typical of biological high-valent metal-oxygen species. Particularly, the Ni(III) complexes were generated in situ, at low temperature, from the oxidation of the Ni(II) species.The nickel complexes studied during this work were supported by tridentate ligands, with a strong σ-donating ability and exceedingly resistant to several common degradation pathways. These complexes vary based on the monodentate group in the fourth coordination position site, which can be neutral or anionic. In particular, we prepared four different Ni(III) complexes [NiIII(pyN2Me2)(OCO2H)] (12), [NiIII(pyN2Me2)(ONO2)] (14), [NiIII(pyN2Me2)(OC(O)CH3)] (18) and [NiIII(pyN2Me2)(OC(O)H)] (25). They feature a bicarbonate (-OCO2H), nitrate (-ONO2), acetate (-OC(O)CH3) and formate (-OC(O)H) group, respectively.HAA and OAT reactions were performed by adding 2,6-di-tert-butylphenol (2,6-DTBP) at -40°C, and triphenylphosphine (PPh3) at -80°C, to the in situ generated Ni(III) complexes, respectively. These reactions were carried out by adding 7 to 500 equivalents of substrate, in order to ensure pseudo-first order conditions. Since, the reactivity of the Ni(III) complex featured by the bicarbonate group has been studied in a previous work, we only investigated that of the species bearing the nitrate, acetate and formate ligand. Finally we compared the value of the reaction rate of all the four species in the HAA and OAT reactions.
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4

Ibrahim, Masooma [Verfasser]. "Polynuclear Transition Metal-Oxo Complexes Stabilized by Heteropolytungstates / Masooma Ibrahim." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2012. http://d-nb.info/1035217686/34.

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5

林曉楓 and Hiu-fung Lam. "Photophysical and photochemical properties of oxo and nitrido complexes of osmium(VI)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B42576490.

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6

Lam, Hiu-fung. "Photophysical and photochemical properties of oxo and nitrido complexes of osmium(VI)." Click to view the E-thesis via HKUTO, 2001. http://sunzi.lib.hku.hk/hkuto/record/B42576490.

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7

Middleditch, Michael. "Towards a catalytic carbonyl olefination reaction using metal oxo complexes and ketenes." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430565.

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8

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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9

鄧煒堂 and Wai-tong Tang. "Homogeneous oxidation of organic substrates by ruthenium, iron and manganese tertiary amine complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31231706.

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10

Tang, Wai-tong. "Homogeneous oxidation of organic substrates by ruthenium, iron and manganese tertiary amine complexes /." [Hong Kong : University of Hong Kong], 1989. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12355203.

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11

Vanover, Eric. "Photochemical Oxidation Studies of Porphyrin Ruthenium Complexes." TopSCHOLAR®, 2012. http://digitalcommons.wku.edu/theses/1201.

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In nature, transition metal containing enzymes display many biologically important, attractive and efficient catalytic oxidation reactions. Many transition metal catalysts have been designed to mimic the predominant oxidation catalysts in nature, namely, the cytochrome P450 enzymes. Ruthenium porphyrin complexes have been the center of this research and have successfully been utilized, as catalysts, in major oxidation reactions, such as the hydroxylation of alkanes. The present work focuses on photocatalytic studies of aerobic oxidation reactions with well characterized ruthenium porphyrin complexes. The photocatalytic studies of aerobic oxidation reactions of hydrocarbons The photocatalytic studies of aerobic oxidation reactions of hydrocarbons catalyzed by a bis-porphyrin-ruthenium(IV) μ-oxo dimer using atmospheric oxygen as the oxygen source in the absence of co-reductants were investigated. The ruthenium(IV) μ-oxo bisporphyrin (3a-d) was found to catalyze aerobic oxidation of a variety of organic substrates efficiently. By comparison, 3d was found to be a more efficient photocatalyst than the well-known 3a under identical conditions. A KIE at 298K was found to be larger than those observed in autoxidation processes, suggesting a nonradical mechanism that involved the intermediacy of ruthenium(V)-oxo species as postulated. The reactivity order in the series of ruthenium(IV) μ-oxo bisporphyrin complexes follows TPFPP>4- CF3TPP>TPP, and is consistent with expectations based on the electrophilic nature of the ruthenium(IV) μ-oxo bisporphyrin species. The trans-dioxoruthenium(VI) porphyrins have been among the best characterized metal-oxo intermediates and their involvement as the active oxidant in the hydrocarbon oxidation have been extensively studied. In addition to the well-known chemical methods, we developed a novel approach for generation of trans-dioxoruthenium( VI) porphyrins with visible light by extension of the known photoinduced ligand cleavage reactions. A series of trans-dioxoruthenium(VI) porphyrin complexes (6a-d) were photochemically synthesized and spectroscopically characterized by UV-vis, and 1H-NMR.
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12

Ducloiset, Clémence. "Etude de complexes pour les réactions par transfert d’atome d’oxygène ou d’azote : de la synthèse à la photoactivation." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS252/document.

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Les processus d’oxydation et d’amination sont très importants dans le monde de l’industrie mais les procédés actuels sont polluants. Afin de réaliser ces transformations de manière catalytique et propre, les réactions bioinspirées par transfert d’atome d’oxygène (TAO) et d’azote (TAN) ont été étudiées. La formation de l’espèce active à haut degré d’oxydation étant bien connue dans le cas des TAO, l’enjeu se situe dans le design des ligands. Dans le cas des TAN, cette étape est moins bien étudiée, limitant le développement de nouveaux catalyseurs. Enfin, l’utilisation d’une source d’énergie lumineuse, et non plus chimique, est recherchée afin de diminuer les déchets produits lors de ces réactions.Deux stratégies ont été mises en œuvre au cours de ce projet. Pour l’étude des réactions par TAO, deux nouveaux jeux de ligands, similaires aux porphyrines et aux BODIPY, ont été synthétisés. L’obtention et la caractérisation des complexes de ruthénium ainsi que leur réactivité par oxydation chimique ou électrochimique ont été réalisées. Pour les réactions de TAN, le mécanisme du dimère connu Rh2(esp)2 de type PCET (transfert couplé de proton et d’électron), semblable à celui des réactions par TAO, a été étudié en identifiant les différents intermédiaires formés grâce à une étude spectro-électrochimique. Ces différentes étapes ont ensuite été réalisées par voie photochimique développant ainsi l’utilisation de l’énergie lumineuse pour réaliser des réactions de TAO et TAN de manière éco-compatible
Processes of oxidation and amination hold an important place on an industrial level but the current available methods are polluting and non-sustainable. To perform these transformations in the contour of green catalysis, bio-inspired oxygen atom transfer (OAT) and nitrogen atom transfer (NAT) reactions were addressed. In the case of OAT, the mechanism for the formation of the active species, the highly oxidized metal-oxo, is rather well described, and the challenge relies in the design of ligands to stabilize such species. For NAT, this step is less studied which limits the development of new catalysts. An even more challenging task resides in the use of light energy to generate these active species in the perspective to replace the classic oxidants. During this thesis, two projects have been undertaken. Firstly, the synthesis of dipyrrin based ligands and the corresponding ruthenium complex was evaluated for their ability to perform OAT reactions using conventional oxidants or the electrochemical way. Regarding the NAT reactions, we have investigated on the electrochemical, chemical and photochemical activation of the known catalyst Rh2(esp)2. Our strategy consisted in the activation of the nitrogen atom donor substrate, the sulfonamidate, in the coordination sphere of the catalyst. We disclose the spectroscopic signatures for the stepwise activation of the catalyst-substrate form. This work has as objective to set us on the path to develop a sustainable way to perform these reactions
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13

Kwong, Ka Wai. "Visible-Light Generation of High-Valent Metal-Oxo Intermediates and a Biomimetic Oxidation Catalyzed By Manganese Porphyrins with Iodobenzene Diacetate." TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1743.

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High-valent iron-oxo intermediates play central roles as active oxidants in enzymatic and synthetic catalytic oxidations. Many transition metal catalysts are designed for biomimetic studies of the predominant oxidation catalysts in Nature, the cytochrome P450 enzymes. In this work, a new photochemical method to generate high-valent iron-oxo porphyrin models was discovered. As controlled by the electronic nature of porphyrin ligands, iron(IV)-oxo porphyrin radical cations (Compound I model) and iron(IV)-oxo porphyrin derivatives (Compound II model) were produced. These observations indicate that the photochemical reactions involve a heterolytic cleavage of O-Br in precursors to give a putative iron(V)-oxo intermediate, which might relax to Compound I through electron transfer from porphyrin to the iron or undergo rapid comproportionation reaction with residual iron(III) to afford the Compound II derivative. Furthermore, visible light photolysis of bis-porphyrins-dimanganese(III)-μ-oxo complexes, [MnIII(Por)]2O, was studied in three porphyrin systems. Direct conversion of manganese(III)-μ-oxo dimers to manganese(IV)-oxo porphyrins [MnIV(Por)(O)] and manganese(III) products was observed in benzene solution upon light irradiation. The spectral signature of [MnIV(Por)(O)] was further confirmed by production of the same species in the reported reaction of the [MnIII(Por)Cl] with PhI(OAc)2. Continuous irradiation of bis-porphyrins-dimanganese(III)-μ-oxo complexes in the presence of pyridine or triphenylphospine gave rise to the formation of [MnII(Por)(Py)] or [MnII(Por)(PPh3)], which are stable to be detected. A photo-disproportionation mechanism similar to that for bis-porphyrins-diiron(III)-μ-oxo complex was proposed to explain above photochemical behaviors of bis-porphyrins-dimanganese(III)-μ-oxo complexes. With iodobenzene diacetate [PhI(OAc)2] as the oxygen source, manganese(III) porphyrin complexes exhibit remarkable catalytic activity towards the selective oxidation of alkenes and activated hydrocarbons. Conspicuous is the fact that the readily soluble PhI(OAc)2 in the presence of a small amount of water is more efficient oxygen source than the commonly used PhIO under same conditions. High selectivity for epoxides and excellent catalytic efficiency with up to 10,000 Turnovers (TONs) were achieved in alkene epoxidations. A manganese(IV)-oxo porphyrin was observed in the oxidation of the manganese(III) porphyrin and PhI(OAc)2. However, catalytic competition and Hammett studies suggested that the more reactive manganese(V)-oxo intermediate was favored as the premier active oxidant, even it is too short-lived to be detected in the catalytic reaction.
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14

Li, Lin [Verfasser]. "Matrix Isolation and IR Spectroscopic Study on Late-Transition Fluorides, Metal Oxo Complexes and Actinide Halides / Lin Li." Berlin : Freie Universität Berlin, 2021. http://d-nb.info/1232726710/34.

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15

Chambers, Matthew Burke. "Ligand field considerations for the reactivity of high valent metal-oxo complexes and of bimetallic HX splitting photocatalysts." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82312.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Inorganic molecular complexes are used to probe mechanistic steps in two reaction reactions related to energy storage. The first reaction considered is the O-O bond formation step required for water oxidation to oxygen. The second reaction considered is the photocatalytic generation of hydrogen and halogen from hydrohalic acid. Regarding the O-O bond formation process, terminal metal oxo complexes of pseudotetrahedral geometry were synthesized and studies focused on determining the electronic structure of these complexes as well as reactivity patterns. A novel series of low coordinate tris(alkoxide) complexes of divalent and trivalent metals were synthesized and characterized as single metal site models of oxidic metal clusters. Via oxygen atom transfer reactions, d⁰, d¹, and d² early transition metal-oxo complexes were stabilized. Analysis of structural parameters, infrared spectroscopy and DFT calculations establish that the first two d electrons fill degenerate [pi]* orbitals with respect to the M-O bond. An electronic structure was determined wherein there is a low lying degenerate dxz, dyz set of orbitals, a more destabilized degenerate set of dxy, dX2-y2 orbital, with dz2 as the most destabilized d orbital. Upon addition of oxygen atom transfer reagents to tris(alkoxide) divalent iron complexes, rapid C-H bond abstraction is observed to afford an Fe(III)-OH moiety. This rapid and indiscriminate nature in which this reaction proceeds is calculated to arise from the production of a terminal Fe(IV) oxo intermediate complex with a quintet spin state. The exceptionally weak ligand field orthogonal to the ferryl is proposed to stabilize a high spin state and promote the reactivity. Regarding HX splitting, a new dirhodium diphosphazane structure is evaluated for photocatalytic HX splitting behavior. The complex photoreduces protons but degrades quickly. Rational ligand modifications afford an indefinitely stable proton reduction photocatalyst. Upon proton reduction from hydrohalic acid, valence isomers of a tetrachloride product were isolated. The efficiencies of halide elimination from the valence symmetric and mixed valent complexes were determined to be similar. Calculations suggest that halogen elimination proceeds through a bridging halide structure and access to this structure is the determining factor for the efficiency of halogen elimination.
by Matthew Burke Chambers.
Ph.D.
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16

Labonnette, Daniel. "Etude des especes du vanadium iv en milieu faiblement acide et alcalin : isopolyanions mixtes mo**(vi)-v**(iv), complexes carbonates de v**(iv)." Orléans, 1987. http://www.theses.fr/1987ORLE2009.

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L'alcalinisation progressive d'une solution acide de vo**(2+) par une base forte, entraine la formation successive des especes : vooh**(+), (vooh)::(2)**(2+) vo(oh)::(2), v::(4)o::(9)h**(-), v::(4)o::(9)h**(-), v::(4)o::(9)**(2-), vo(oh)::(3)**(-) et des ions polycondenses en milieu fortement basique et tres concentre en v(iv). Quand l'alcalinisation est realisee par hco::(3)**(-) ou co::(3)**(2-), il y a formation de complexes carbonato
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17

Henry, Marc. "Application du concept d'electronegativite aux processus d'hydrolyse et de condensation en chimie minerale." Paris 6, 1988. http://www.theses.fr/1988PA066293.

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Utilisation des procedes sol-gel pour elabour des materiaux a base d'oxydes et a proprietes optimisees. Mecanismes d'hydrolyse et de condensation des precurseurs moleculaires (alcoxydes ou sels metalliques) aboutissant a l'obtention de materiaux mixtes organiques/inorganiques
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18

Giraudon, Jean-Marc. "Complexes mono et dinucléaires du molybdene avec les ligands macrocycliques : synthèse, structure, réactivité et propriétés redox." Brest, 1988. http://www.theses.fr/1988BRES2019.

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Preparation des complexes avec le coordinat tetraazaannulene; cas de complexes a liaison quadruple du mo ou le coordinat organique presente une coordination tetradentee. On envisage les mecanismes d'interconversion monomere oxo-dinucleaire. Etudes rpe et uv-visible
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19

Meyer, Jonathan [Verfasser], and Gereon [Akademischer Betreuer] Niedner-Schatteburg. "Fragmentation and Infrared Spectroscopy of oxo-centered Homo- and Heterotrimetallic Carboxylate Bridged Transition Metal Complexes / Jonathan Meyer ; Betreuer: Gereon Niedner-Schatteburg." Kaiserslautern : Technische Universität Kaiserslautern, 2019. http://d-nb.info/1175950440/34.

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20

Meyer, Jonathan Ruben [Verfasser], and Gereon [Akademischer Betreuer] Niedner-Schatteburg. "Fragmentation and Infrared Spectroscopy of oxo-centered Homo- and Heterotrimetallic Carboxylate Bridged Transition Metal Complexes / Jonathan Meyer ; Betreuer: Gereon Niedner-Schatteburg." Kaiserslautern : Technische Universität Kaiserslautern, 2019. http://d-nb.info/1175950440/34.

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21

Ayad, Massinissa. "Réactivité biomimétique du dioxygène au sein de complexes du fer et du cuivre en vue de l’activation des liaisons C-H." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0054.

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L’oxydation catalytique des liaisons C-H, en condition aérobie est l’une des réactions « phare » de la chimie, aussi bien d’un point de vue fondamental qu’industriel. Le principal défi consiste en l’utilisation de l’oxygène moléculaire comme oxydant « vert » pour l’activation de ces liaisons C-H. De nombreuses métalloprotéines, telles que les mono-oxygénases (Fe, Cu), sont capables de réaliser ces réactions dans des conditions douces. Une stratégie actuelle consiste à développer des systèmes synthétiques capables de reproduire de manière efficace les propriétés catalytiques de ces enzymes. L’objectif principal de nos travaux a été de synthétiser et de caractériser des modèles de mono-oxygénases solubles (sMMO) et membranaires (pMMO). Deux approches ont été développées. La première a consisté à élaborer des ligands ditopiques dissymétriques, dont les deux sites de coordination tris-(2-pyridymethyl)amine “TPA” et pyridinedicarboxamide “PydCA”, sont enclavés dans un seul macrocycle afin de favoriser une distance intermétallique optimale. La seconde stratégie est basée sur la synthèse de ligands ditopiques où les motifs coordinants, tetraazacyclotetradecane “cyclam” et dipicolylamine “DPA”, sont séparés par un espaceur de type phényle. Ces deux approches ont conduit à l’obtention et à la caractérisation, à l’état solide (structure aux rayons X) et en solution (spectroscopie, électrochimie), de nombreux complexes mono et dinucléaires du fer, du cuivre et du cobalt. L’étude de la réactivité de certains complexes mononucléaires vis-à-vis des oxydants tels que O2 et H2O2, en l’absence de substrats organiques, a permis d’identifier des espèces métal-oxygène. L’oxydation catalytique de substrats organiques a également été réalisée
Catalytic oxydation of C-H bonds using molecular oxygen as ‘green’ oxidant remains a great challenge from both fundamental and industrial point of views. Many metalloproteins, such as copper end iron-based mono-oxygenases are able to perform these reactions under mild conditions. A current strategy is to develop synthetic complexes which can reproduce the efficiency of such enzymes. The main objective of our work has been to synthesize and characterize new models of soluble (sMMO) and particulate (pMMO) mono-oxygenases. Two approaches have been developed. The first strategy was to synthesize unsymmetrical dinucleating ligands bearing two coordination sites, tris-(2-pyridylmethyl)amine “TPA” and pyridinedicarboxamide “PydCA”, which are embedded in a single macrocycle to favor intermetallic interaction. The second strategy is based on the synthesis of dinucleating ligands where coordinating patterns, tetraazacyclotetradecane “cyclam” and dipicolylamine “DPA”, are separated by a phenyl type spacer. These two approaches have led to the formation and characterization in the solid state (X-ray structure) and in solution (spectroscopy, electrochemistry) of many mononuclear and dinuclear iron, copper and cobalt complexes. The study of the reactivity of some mononuclear complexes towards oxidants such as O2 and H2O2, in absence of organic substrates, has led to the identification of metal-oxygen species. Catalytic oxidation of organic substrates was also conducted
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22

Stewart, Peter John. "Metal-ligand multiply bonded complexes supported by amidinate ligands." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243747.

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23

Benkada, Assma [Verfasser], Wolfgang [Akademischer Betreuer] Bensch, and Norbert [Gutachter] Stock. "Synthesis of Thiostannates, Oxo-Thiostannates and Tin-Sulfides Applying Transition Metal Complexes Containing Macrocyclic Amine Molecules : Development of new synthetic routes to synthesize Sn-S and S-Sn-O compounds and investigation of their properties / Assma Benkada ; Gutachter: Norbert Stock ; Betreuer: Wolfgang Bensch." Kiel : Universitätsbibliothek Kiel, 2020. http://d-nb.info/1222974169/34.

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24

Huang, Yan. "Synthesis, Kinetic and Photocatalytic Studies of Porphyrin-Ruthenium-Oxo Complexes." TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/182.

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Macrocyclic ligand-complexed transition metal-oxo intermediates are the active oxidizing species in a variety of important biological and catalytic oxidation reactions. Many transition metal catalysts have been designed to mimic the predominant oxidation catalysts in Nature, namely the cytochrome P450 enzymes. Ruthenium porphyrin complexes have been the center of the research and have successfully been utilized, as catalysts, in major oxidation reactions such as the hydroxylation of alkanes. This study focuses on kinetic and photocatalytic studies of oxidation reactions with wellcharacterized high-valent ruthenium-oxo porphyrin complexes. The trans-dioxoruthenium(VI) porphyrins have been among the best characterized metal-oxo intermediates and their involvement as the active oxidant in the hydrocarbon oxidation have been extensively studied. Following the literature known methods, a series of trans-dioxoruthenium(VI) porphyrin complexes (3a-b) were synthesized and spectroscopically characterized by UV-vis, IR and lH-NMR. In addition to the well-known chemical methods, we developed a novel photochemical approach for generation of trans-dioxoruthenium(VI) porphyrins with visible light. The fast kinetic study of two-electron oxidations of para-substituted phenyl methyl sulfides by these dioxoruthenium(VI) species was conducted by using stopped-flow spectroscopy. Results showed that the decay of trans--dioxoruthenium(VI) porphyrins in the presence of reactive sulfides follows a biexponential process. The reactivity order in the series of dioxoruthenium complexes follows TPFPP> TPP> TMP, consistent with expectations based on the electrophilic nature of high-valent metal-oxo species. Moreover, the sulfoxidation reactions are 3 to 4 orders of magnitude faster than the well-known epoxidation reactions. In addition, several ruthenium porphyrins were used as the catalysts in the competitive oxidation reactions to identify the kinetically competent oxidants during catalytic turnover conditions. The photocatalytic studies of aerobic oxidation reactions of hydrocarbons catalyzed by a bis-porphyrin-ruthenium(lV) fl-OXO dimer using atmospheric oxygen as oxygen source in the absence of co-reductants were investigated as well. The ruthenium(lV) fl-OXO bisporphyrin (6a) was found to catalyze aerobic oxidation of a variety of organic substrates efficiently. By comparison, 6a was found to be more efficient photocatalyst than the well-known 3a under identical conditions. A KIE at 298K was found to be larger than those observed in autoxidation processes, suggesting a nonradical mechanism that involved the intermediacy of ruthenium(V)-oxo species as postulated.
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25

張碧玉 and Pik-yuk Christine Cheung. "Crystal structure analysis of imido, nitrido and oxo complexes of rhenium (V), osmium (VI) and ruthenium (III) and some complexes oftrinuclear gold (I)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31210211.

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26

Cheung, Pik-yuk Christine. "Crystal structure analysis of imido, nitrido and oxo complexes of rhenium (V), osmium (VI) and ruthenium (III) and some complexes of trinuclear gold (I) /." [Hong Kong : University of Hong Kong], 1991. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13138327.

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27

Delony, Daniel. "Proton Coupled Electron Transfer at Heavy Metal Sites." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1546-5.

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28

Jäger, Norbert. "Molekülmechanische und quantenchemische Berechnung der räumlichen und elektronischen Struktur von Vanadium(IV)- und Oxo-Rhenium(V)-Chelaten dreizähnig diacider Liganden." Phd thesis, Universität Potsdam, 1998. http://opus.kobv.de/ubp/volltexte/2005/154/.

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In dieser Arbeit wurden die Molekülstrukturen und die elektronischen Eigenschaften von Vanadium(IV)- und Oxo-Rhenium(V)-Chelaten mit einem kombinierten molekülmechanisch-quantenchemischen Ansatz untersucht, um sterische und elektronische Effekte der Komplexierung mit einem theoretischen Modell zu quantifizieren. Es konnte gezeigt werden, daß auf diese Weise detaillierte Aussagen zu den Bindungsverhältnissen der Metallchelate getroffen werden können. Die Berechnung der Molekülstrukturen gelingt mit exzellenter Übereinstimmung mit den Kristallstrukturen der Komplexe. Die molekülmechanischen Berechnungen erfolgen auf der Grundlage des Extensible Systematic Force Field ESFF und des Consistent Force Field 91 (CFF91). Dabei konnte die hohe Flexibilität und Zuverlässigkeit des regelbasierten ESFF für eine Vielzahl verschiedenster Metallchelate nachgewiesen werden. Aufgrund der mangelhaften Ergebnisse für trigonal-prismatische Komplexgeometrien mit dem ESFF wurden eine Anpassung des CFF91 für derartige Vanadiumkomplexe vorgenommen. Auf Grundlage von theoretischen Ergebnissen wurden die alternativen Strukturen von isoelektronischen Vanadiumkomplexen berechnet und in Übereinstimmung mit experimentellen Daten, theoretischen Modellen der Komplexchemie und empirischen Fakten eine Hypothese für die Ursache der strukturellen Differenzen erarbeitet.
Der hier vorgestellte, kombinierte Algorithmus aus kraftfeldbasierter Geometrieoptimierung und single-point-Rechnung an diesen Strukturen ist ein zuverlässiger und relativ schneller Weg Molekülgeometrien von Metallkomplexen zu berechnen. Er kann somit zur Voraussagen von Komplexstrukturen und zur gezielten Modellierung definierter Koordinationsgeometrien verwendet werden.
In this work the molecular structures and the electronic properties of Vanadium(IV)- and Oxo-Rhenium(V)-chelates have been investigated to quantify steric and electronic effects of complexation. It has been shown, that in this way detailed insight can be gained into the bonding conditions of that metal complexes. Molecular mechanic calculations based on the Extensible Systematic Force Field (ESFF) and the Consistent Force Field 91 (CFF91) have been carried out. High flexibility and reliability of the rule based ESFF has been proven for a large variety of different metal chelates. Due to the poor ESFF-results for trigonal-prismatic complex geometries, a fit of the CFF91 for that species was done. Based on the theoretical results the alternative structure of isoelectronical vanadium(IV)- complexes have been calculated and a hypothesis on the reason for the structural differnces have been stated in accordance with experimental results, theoretical models of complex chemistry, and empirical facts. This combined approach of force field based geometry optimization and single point calculation at these structures has been proven to be a reliable and fast way to get molecular structures of metal complexes. It can be used to predict complex structures for modelling destinct coordination geometries.
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29

Da, Re Ryan Edward. "Electronic spectra and structures of metal-oxo complexes /." 2002. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3039022.

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30

"Part I. Studies of octasubstituted Oxo(phthalocyaninato)titanium(IV) complexes: Part II. Dioxotungsten(VI) complexes with N2O2 and N2S2 tetradentate ligands." 1996. http://library.cuhk.edu.hk/record=b5889192.

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Abstract:
by Wing-Fong Law.
Year shown on spine: 1997.
The "2" in the title is subscript.
Thesis (M.Phil.)--Chinese University of Hong Kong, 1996.
Includes bibliographical references (leaves 103-110).
ACKNOWLEDGMENT --- p.i
CONTENTS --- p.ii
LIST OF FIGURES --- p.v
LIST OF TABLES --- p.vii
ABBREVIATIONS --- p.viii
ABSTRACT --- p.x
Chapter I. --- STUDIES OF OCTASUBSTITUTED OXO(PHTHALOCYANINATO) TITANIUM(IV) COMPLEXES
Chapter 1. --- INTRODUCTION --- p.2
Chapter 2. --- RESULTS AND DISCUSSION
Chapter 2.1. --- Preparation of Substituted Dicyanobenzenes and Dicyanonaphthalene --- p.9
Chapter 2.2. --- Synthesis of Octasubstituted Oxo(phthalocyaninato)titanium(IV) and (Naphthalocyaninato)oxotitanium(IV) Complexes --- p.12
Chapter 2.3. --- "Solvent Effects on the UV-Vis Absorption Spectra of (2,3,9,10,16, 17,23,24-Octaheptylphthalocyaninato)oxotitanium(IV)" --- p.27
Chapter 2.4. --- Aggregation of Octasubstituted Oxo(phthalocyaninato)titanium(IV) and (Naphthalocyaninato)oxotitanium(IV) Complexes --- p.29
Chapter 2.5. --- Electrochemical Studies of Octasubstituted Oxo(phthalocyaninato)- titanium(IV) and (Naphthalocyaninato)oxotitanium(IV) Complexes --- p.34
Chapter 2.6. --- Reactions of Disubstituted Dicyanobenzenes with Zirconium(IV) Butoxide and Urea --- p.39
Chapter 2.7. --- Conclusion --- p.40
Chapter 3. --- EXPERIMENTAL SECTION
Chapter 3.1. --- Materials --- p.42
Chapter 3.2. --- Physical Measurements --- p.42
Chapter 3.3. --- "Preparation of l,2-Dicyano-4,5-diheptylbenzene" --- p.43
Chapter 3.4. --- "Preparation of l,2-Dicyano-4,5-bis(pentyloxy)benzene" --- p.45
Chapter 3.5. --- "Preparation of l,2-Dicyano-4,5-bis(alkoxymethyl)benzene" --- p.47
Chapter 3.6. --- "Preparation of 3,6-Bis(butyloxy)-l,2-dicyanobenzene" --- p.49
Chapter 3.7. --- "Preparation of 2,3-Dicyano-5,8-dihexylnaphthalene" --- p.50
Chapter 3.8. --- Preparation of Octasubstituted Oxo(phthalocyaninato)titanium(IV) Complexes --- p.52
Chapter 3.9. --- Preparation of Octasubstituted (Naphthalocyaninato)oxotitanium(IV) Complex --- p.57
Chapter 3.10. --- Miscellaneous Syntheses --- p.58
Chapter II. --- dioxotungsten(vi) complexes with n202 and n2s2 tetradentate ligands
Chapter 1. --- INTRODUCTION --- p.62
Chapter 2. --- RESULTS AND DISCUSSION
Chapter 2.1. --- Preparation of Tetradentate Ligands --- p.75
Chapter 2.2. --- Preparation of Dioxotungsten(VI) Complexes --- p.78
Chapter 2.3. --- Electrochemical Studies of Dioxotungsten(VI) Complexes --- p.86
Chapter 2.4. --- Oxo-transfer Properties of Dioxotungsten(VI) Complexes --- p.91
Chapter 2.5. --- Conclusion --- p.94
Chapter 3. --- EXPERIMENTAL SECTION
Chapter 3.1. --- Materials --- p.95
Chapter 3.2. --- Physical Measurements --- p.95
Chapter 3.3. --- Preparation of Tetradentate Ligands --- p.96
Chapter 3.4. --- Preparation of Dioxotungsten(VI) Complexes --- p.100
REFERENCES --- p.103
APPENDIX A lH NMR spectra of Pc'TiOs --- p.111
APPENDIX B 13C{1H} NMR spectra of octasubstituted PcTi compounds --- p.113
APPENDIX C Mass spectra of octasubstituted PcTi and PcZr compounds --- p.118
"APPENDIX D IR spectra of octasubstituted PcTi, NcTi and PcZr compounds" --- p.124
APPENDIX E Cyclic voltammograms of octasubstituted PcTiOs and NcTiO --- p.131
APPENDIX F Determination of aggregation number (n) and aggregation constant (K) --- p.136
APPENDIX G 1H NMR spectra of dioxotungsten(VI) complexes --- p.138
APPENDIX H 13C{1H} NMR spectra of dioxotungsten(VI) complexes --- p.140
APPENDIX I LSI mass spectra of dioxotungsten(VI) complexes --- p.143
APPENDIX J IR spectra of dioxotungsten(VI) complexes --- p.147
APPENDIX K Crystallographic data of W02(L2-N202) (64) --- p.150
APPENDIX L Kinetic data for the oxo-transfer reactions --- p.160
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31

Lay, Nien-Sheng, and 賴年盛. "Intermetal Oxo Transter :Isomerization of Mixed-Metal W-Re Car- bonyl, Complexes with Oxo and Acetylide Ligands." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/36410939292605689553.

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32

Khownium, Kriangsak. "Direct atom transfer vs. ring expansion in reaction of rhenium oxo complexes with cyclooctene epoxides and episulfides." Thesis, 2003. http://hdl.handle.net/1957/29849.

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