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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

New aspects of organometallic chemistry /

Williams, Michael Lloyd. January 1985 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, 1985. / Includes bibliographical references (leaves 204-208).
22

Cyclopentadienyl ruthenium chemistry /

Wallis, Robert Charles. January 1981 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1982. / Typescript (photocopy).
23

Aspects of organometallic chemistry, particularly metal alkynyl and cluster chemistry /

Humphrey, Mark Graeme. January 2002 (has links) (PDF)
Thesis (D.Sc.)--University of Adelaide, Dept. of Chemistry, 2003. / Includes bibliographical references.
24

Ruthenium-carbon bonding interaction synthesis and spectroscopic studies of ruthenium-acetylide, -carbene, -vinylidene and -allenylidene complexes

Wong, Chun-yuen. January 2004 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
25

Ruthenium-carbon bonding interaction synthesis and spectroscopic studies of ruthenium-acetylide, -carbene, -vinylidene and -allenylidene complexes

Wong, Chun-yuen., 黃駿弦. January 2004 (has links)
published_or_final_version / abstract / toc / Chemistry / Doctoral / Doctor of Philosophy
26

New aspects of organometallic chemistry / by Michael Lloyd Williams

Williams, Michael Lloyd January 1985 (has links)
Bibliography: leaves 204-208 / 208 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1985
27

Designing and investigating molecular bistability in ruthenium dimethylsulfoxide complexes /

Rachford, Aaron A. January 2007 (has links)
Thesis (Ph.D.)--Ohio University, June, 2007. / Includes bibliographical references (leaves 186-191)
28

Oxidations using dioxoruthenium (VI)-porphyrin complexes ; and studies on some organoruthenium-porphyrin species

Rajapakse, Nimal January 1990 (has links)
The oxidation of three alkyl thioethers, phenol and 2-propanol by trans-dioxo ruthenium porphyrin species, and the synthesis, characterization and reactivity of several new ruthenium porphyrin complexes are described in this thesis. The trans-dioxo species Ru(Porp)(O)₂ [Porp= the dianions of 5,10,15,20-tetramesitylporphyrin (TMP) and 5,10,15,20-(2,6-dichlorophenyl)porphyrin (OCP)] selectively oxidize diethyl-, di-n-butyl- and decylmethyl- sulfides to the corresponding sulfoxides at room temperature. The reaction is first order in [Ru] and in [thioether]. The second order rate constants for the first O-atom transfer from the Ru(TMP) system are: 7.54xl0⁻³, 1.23xl0⁻² and 1.14x10-¹ M⁻¹ s⁻¹ respectively for the three thioethers at 20.0 °C. The activation parameters for the O-atom transfer process are also determined: for Et₂S, ∆H‡= 58.3 kJ mol⁻¹ and ∆S‡= -86 J K⁻¹ mol⁻¹; for nBu₂S, AH‡= 47.4 kJ mol⁻¹and ∆S‡= -120 J K⁻¹ mol⁻¹; for DecMeS, ∆H‡= 56.5 kJ mo⁻¹ and ∆S‡= -70 J K⁻¹ mol⁻¹. A second order rate constant of 7.23xl0⁻²M⁻¹s⁻¹ is measured at 20.0 °C for the oxidation of Et₂S by Ru(OCP)(O)₂. The intermediates Ru(TMP)(OSEt₂)₂, Ru(TMP)(OSEt₂)(OSEt₂) and the final product Ru(TMP)(0SEt₂)₂,where O and S refer to O- and S- bonded sulfoxide, are observed by ¹H nmr, and the last mentioned is isolated and characterized. A mechanism is proposed, based on electrophilic attack of the O=Ru=O moiety on :SR₂ to form bis-O-bonded species which subsequently isomerizes to bis-S-bonded species via mixed species. The Ru(TMP)(O)₂/Et₂S/O₂ system at room temperature is catalytic in complex, but produces only about 5 turnovers due to poisoning of the catalyst by the reaction product. The same system at >65 °C gives higher turnovers, but now porphyrin ligand degradation is observed, perhaps via oxidation by the O=Ru=O moiety. The Ru(OCP)(0)₂/Et₂S/O₂ system at 100 °C catalytically oxidizes Et₂S to Et₂SO and Et₂SO₂ (in ~ 4:1 ratio) and the porphyrin ligand does not undergo oxidative destruction. The Ru(TMP)(O)₂ species reacts with phenol via an observed intermediate Ru(TMP)(p-O(H)C₆H₄OH)₂ to form Ru(IV)(TMP)(OC₆H₄OH)₂, a paramagnetic (S=l) complex which is isolated and characterized. The oxidation reaction is first order in both [Ru] and [phenol] with a second order rate constant 6.90x10⁻² M⁻¹ s⁻¹at 20.0 °C. A mechanism based on electrophilic attack by the O=Ru=O moiety on the aryl ring followed by proton migration is proposed. This mechanism also explains the formation of some free para-benzoquinone and 1 equivalent of water per Ru. No ortho-benzoquinone is formed in the reaction. Preliminary ⁻H nmr studies reveal that 2-propanol is oxidized to acetone by Ru(TMP)(O)₂. A paramagnetic species (S= 1) was isolated as the only porphyrin product but not characterized. A range of novel ruthenium porphyrin complexes is also prepared. The reaction of acetylene with the four-coordinate Ru(TMP) species forms [Ru(TMP)]₂(u-C₂H₂), the first reported organometallic ruthenium porphyrin dimer. The complexes, Ru(TMP)(PhCCPh) and Ru(TMP)(PhCCH), the first π-bonded alkyne species in ruthenium porphyrin chemistry, are characterized in solution. The π-bonded alkene complexes Ru(TMP)(CH₂CH₂) OPrOH).(iPrOH) and Ru(TMP)(CH₂CH₂) are isolated and characterized, while the Ru(TMP)(cyclohexene) complex is characterized in situ. The Ru(TMP)(OSEt₂)₂ complex is isolated also by the reaction of Ru(TMP)(CH₃CN)₂with Et₂SO. The Ru(TMP)(L)₂ complexes, L= OSMe₂, OSnPr₂ and OSnBu₂ are also prepared via the above method and characterized. Some new Ru(OCP) complexes, (the monocarbonyl, the bis-acetonitrile and the dioxo- species) are also isolated and characterized. / Science, Faculty of / Chemistry, Department of / Graduate
29

From olefin metathesis to organoruthenium homogeneous catalysis : synthesis, applications and mechanistic understanding

Manzini, Simone January 2014 (has links)
Olefin metathesis is a valuable synthetic tool, widely used in several fields of science. Due to the importance of this transformation several contributions have been made in this field in order to understand mechanistic aspects, reactivity and applicability of this process. In this topic, ruthenium indenylidene complexes have shown great activity and stability in metathesis, making them very valuable pre-catalysts. However, several aspects of these pre-catalysts have not been evaluated yet. For example, even though reports of active second generation ruthenium indenylidene complexes bearing bulky N-heterocyclic carbenes are present in the literature, no studies have been done to understand how steric hindrance affects the process. For these reasons, [RuCl₂(IPr*)(PPh₃)(3-phenylindenylidene)] (IPr*-PPh₃) and [RuCl₂(IPr*)(Py)(3-phenylindenylidene)] (IPr*-Py), bearing the very bulky ligand, IPr* have been synthesised and compared with [RuCl₂(IPr)(PPh₃)(3-phenylindenylidene)] (IPr-PPh₃) and the new [RuCl₂(IPr)(Py)(3-phenylindenylidene)] (IPr-Py). Another important aspect, presented in this thesis, is the investigation of the stability of indenylidene pre-catalysts in alcohol solvents. Surprisingly, several different decomposition processes occur depending on the starting complex and the alcohol used. Mechanistic investigation into this decomposition, allowed us to develop a better understanding of this process, and to predict the decomposition product based on the environment. In particular, this study revealed that [RuCl(η⁵-3-phenylindenyl)(PPh₃)₂] (Eta-5) is accessed from [RuCl₂(3-phenylindenylidene)(PPh₃)₂] (M₁₀) via a novel indenylidene to η⁵-indenyl rearrangement. This formal decomposition product has been found to be active in at least 20 different catalytic transformations, rendering it a versatile catalytic tool.
30

Triphenylmethylium-based multitopic two-photon absorbers : synthesis and characterization / Absorbeurs Bi-photoniques multitopiques dérivés du triphenylmethane cation : synthèse et caractérisation

Ripoche, Nicolas 20 November 2015 (has links)
Au cours de cette thèse, de nouveaux dérivés organométalliques basés sur une structure triphénylméthylium ont été synthétisés. Ces composés, notamment grâce à leur structure multiplolaire, sont pressentis pour avoir des propriétés remarquables en optiques non linéaire (ONL) qui pourraient donner lieu à des développements appliqués dans plusieurs domaines. Ces caractéristiques, et plus précisément leur absorption biphotonique (A2P), en font des composés particulièrement intéressants pour l'industrie de pointe (microfabrication, imagerie, dispositifs optiques, etc.). Cependant, ces propriétés d'ONL et d'absorption biphotoniques n'ont été jusqu’à lors que peu étudiées, malgré leur potentiel prometteur. Dans un premier temps, une famille de nouveaux composés organiques présentant cette structure particulière, a donc été synthétisée afin de confirmer le potentiel d'absorption à deux photons de ces chromophores, notamment par des mesures Z-scan. Dans un second temps, la synthèse de d’analogues organométalliques ayant des groupes donneurs tels que «Fe(η5-C5Me5)(κ2-dppe)C≡C− , « Ru(Cl)(κ2-dppe)2C≡C− » ou ethynylferrocene a été réalisée et ces dérivés ont été extensivement caractérisés. Ces dérivés organométalliques devraient présenter des sections efficaces d’A2P (ainsi que des réponses ONL de troisième ordre) dans le proche-IR bien supérieures à celles de leurs analogues organique. De plus les groupements métalliques redox-actifs devraient permettre d’obtenir des chromophores électro-commutables. Dans cet objectif, les études déjà réalisées sur ces composés joints à l’étude à venir de leur propriétés ONL de troisième ordre et permettra de mieux comprendre les phénomènes electroniques sous-jacents à ces propriétés et le rôle joué par les parties organique et organométalliques de leur structure. / During this PhD, new organic and organometallic triphenylmethylium dyes were synthesized. Due to their multipolar structure, these compounds have been anticipated to possess strong nonlinear optical (NLO) properties which could be of interest in many fields. These characteristics, and more precisely their two-photon absorption (TPA) properties, make them attractive for the design of high technology materials (microfabrication, imaging, optical devices, etc…). However, their multiphoton absorption properties and other related nonlinear optical (NLO) effects have not been thoroughly investigated to date, in spite of their promising potential. In this respect, a family of organic derivatives has been synthesized to confirm their potential as two-photon absorbers, which was established thanks to Z-scan measurements. Organometallic compounds bearing electron-releasing groups such as «Fe(η5-C5Me5)(κ2-dppe)C≡C−» , « Ru(Cl)(κ2-dppe)2C≡C− » or ethynylferrocene were then synthesized and fully characterized. These organometallic dyes should possess larger TPA cross-sections (and also larger third-order NLO properties) in the NIR range than their organic counterparts. Furthermore, these redox-active metal centers permit access to electro-switchable molecules. In this respect, along with the data already gathered on these derivatives, the study of their cubic NLO properties in their different redox states will now contribute to a better understanding of the underlying electronic phenomena and the role played by the organic and organometallic moieties in such architectures.

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