This thesis describes the results of re-investigations into the solution behavior and interaction with molecular hydrogen of several triarylphosphine and -arsine complexes of ruthenium(ll) and ruthenium(III) The complex RuCl₂(PPh₃)₃ was found to exist in N,N-dimethyl-acetamide (DMA) solutions in equilibrium with, a triply chloro-bridged bis(phosphine) dimer, I (L = DMA). Addition of chloride ion caused [Figure 1] substitution of the solvent to form an anionic dimer, I (L = CI ), and this is discussed, with respect to the stability of this bridging arrangement. In the presence of added base, Proton Sponge® (1,8-bis(dimethyl- amino)naphthalene) , the complexes RuX₂YL₂ (X = Y = CI, Br, or X = CI, Br, Y = 0₂CR; L = PPh₃, Ptol₃, or AsPB₃), [RuCl₂ (PPh₃)₂]₂, [RuCl(DMA)(PPh₃)₂(0₂CCH₂)]₂, and HRuCl(nbd)(PPh₃)₂ were found to react with H₂ in DMA or toluene to give complexes of the form [H₂RuXL₂]₂ (X = CI, Br). The ruthenium(III) product. [H₂RuCl(Ptol₃)₂]₂ has been characterized by analytical, molecular weight, ¹H- and ³¹P-n.m.r. methods and chemical reactions, and the data indicate an asymmetric dichloro-bridged dimer, II. The reaction of II with Ptol₃ in DMA to form HRuCl(Ptol₃)₃ has been studied kinetically; the results suggest that II is in equilibrium with the ruthenium(ll) dimer, [HRuClCPtol₃)₂]₂. The reaction between RuCl₂(PPh₃)₃ and H₂ in DMA to form HRuCl(PPh₃)₃ has also been re-investigated. In the presence of a large excess of PPh₃, the reaction is believed to proceed by way of a bis(phosphine) monomer species, consistent with previous findings. However, in the presence of excess chloride, where the precursor exists as I (L = CI⁻), spectrophotometry evidence indicates the presence of a long-lived intermediate. Investigations .of the v corresponding bis (phosphine) complex, [RuCl₂(PPh₃)₂]₂, have made it possible to formulate the nature of the intermediate. Based mainly on ³¹P-n.m.r. and hydrogen uptake data, the intermediate is believed to be H₃Ru₂Cl₃(PPh₃)₄, a cogener of II. This allows for an overall scheme for the tris(phosphine) system under the conditions of excess chloride: [Figure 2] A similar scheme can be invoked to explain the reactivity of the bis-(phosphine) system. Investigations of the corresponding reactivity toward H₂ of other bis(phosphine) systems for comparison led to the discovery of a new method of preparing carboxylato complexes. Based on a presumed, but not detected, alkyl intermediate, it was possible to prepare the dimer [RuCl(DMA)(PPh₃)₂(O₂CCH₂]₂, containing a bridging succinic acid linkage, and a series of RuCl(0₂CR)(PPh₃)₃ complexes. These have been characterized and their reactivity towards in toluene investigated. At concentrations sufficiently high for n.m.r. studies, the tris(phosphine) species react with to form HRuCl(PPh₃)₃ by a pathway involving initial formation of HRu(₂CR) (PPh₃)₃. The bis (phosphine) system, [RuCl(DMA)(PPh₃)₂(O₂CCH₂)]₂, forms the tetrahydride dimer, II, but the mechanism of formation could not be elucidated. The nature of HRuCl(nbd)(PPh₃)₂ has be en examined; the species possesses the coplanar arrangement of metal, hydride, and olefin deemed requisite for olefin insertion reactions. Indeed, reaction with CO gives an acyl-dicarbonyl derivative, III, which results from consecutive olefin and CO insertion reactions. The HRuCl(nbd)(PPh₃)₂ complex reacts [Figure 3] cleanly with hydrogen in the absence of added base in toluene to form [H₂RuCl(PPh₃)₂]₂. Studies show that the reaction proceeds by a disproportionate reaction to form HRuCl(PPh₃)₃ and subsequent conproportionation with an unobserved phosphine deficient species to form the final product. / Science, Faculty of / Chemistry, Department of / Graduate

Berlin, Freie Universiẗat, Diss., 2003. / Dateiformat: zip, Dateien im PDF-Format.

Berlin, Freie University, Diss., 2000. / Dateiformat: zip, Dateien im PDF-Format.

by Lo Tim Lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 68-71). / Abstract also in Chinese. / Acknowledgments --- p.i / Abstract --- p.ii / Abbreviations --- p.iii / Table of Contents --- p.iv / Chapter Part 1. --- "Arene Oxidation with 2,6-Dichloropyridine- N-oxide Catalyzed by Ruthenium Porphyrins" --- p.1 / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Natural Occurrence of Cytochrome P-450 --- p.1 / Chapter 1.2 --- Biomimetic Models of Cytochromes of P-450 --- p.4 / Chapter 1.3 --- Homogenous Metalloporphyin Catalyzed Oxidation Mimicking Cytochrome P-450 --- p.5 / Chapter 1.4 --- Synthetic Porphyrin Revolution: Third Generation of Porphyrins --- p.6 / Chapter 1.5 --- Fourth-Generation of Porphyrins --- p.9 / Chapter 1.6 --- Variation of Oxygen Donors and Bound Transition Metals --- p.11 / Chapter 1.7 --- Objective --- p.12 / Chapter 2. --- Results and Discussion --- p.15 / Chapter 2.1 --- Synthesis of β-tetraaryl Substituted Mesitylporphyrin and their Ruthenium Carbonyl Complexes --- p.15 / Chapter 2.2 --- "Oxidation of Aromatic Compounds Catalyzed by Ruthenium Porphyrins in 2,6-Dichloropyridine N-oxide System" --- p.17 / Chapter 2.3 --- "Synthesis of trans-Dichloro-tetrakis(p-chlorophenyl)- tetramesitylporphyrinato Ruthenium(IV) Complex, trans- RuTMP(p-ClPh)4(Cl2)" --- p.21 / Chapter 2.4 --- "Oxidation of Aromatic Compounds Catalyzed by trans- Ru(TMP)(p-ClPh)4(Cl2) with 2,6-Dichloropyridine N- oxide" --- p.24 / Chapter 2.5 --- "Effect of Additives to the Catalytic Oxidation of Aromatic Compound by Ru(por)-2,6-Dichloropyridine N- oxide" --- p.24 / Chapter 2.6 --- "Effect of Lewis Acids on the Catalytic Oxidation of Aromatic Compound by Ru(por)-2,6-Dichloropyridine N- oxide" --- p.27 / Chapter 3. --- Conclusion --- p.29 / Chapter 4. --- Experimental Section --- p.30 / Chapter 5. --- Reference --- p.39 / Chapter Part 2. --- Imine Complexes of Ruthenium and Manganese with Acyclic Tetradenate N202-Donors as Oxidation Catalysts for Styrene Epoxidation --- p.42 / Chapter 1 --- Introduction --- p.42 / Chapter 1.1 --- Salen-type Metal Complexes with N202 Anionic Donor Set --- p.43 / Chapter 1.2 --- High-valent Ruthenium Complexes with π-Aromatic Imine Ligand --- p.45 / Chapter 1.3 --- Objective --- p.47 / Chapter 1.3.1 --- Metal Complexes of Phenanthroline-π-aromatized Imlne --- p.47 / Chapter 1.3.2 --- Ruthenium Complex of Jacobsen Ligand --- p.48 / Chapter 2 --- Results and Discussion --- p.50 / Chapter 2.1 --- "Synthesis of cis-Dicarbonyl-[(R,R)-N, N,-bis(3,5-di-tert- butylsalcylidene)-1,2-cyclohexanediaminato (2-)] Ruthenium(II) Complex" --- p.50 / Chapter 2.2 --- "Synthesis of 2,9-Bis(3,5-di-tert-butyl-2-hydroxyphenyl)- 1,10-phenanthroline and Its Manganese and Ruthenium Complexes" --- p.55 / Chapter 2.3 --- Epoxidation of Styrene Catalyzed by Manganese and Ruthenium Phenanthroline Complexes with Hyprochlorite as Oxidant in Different pH Media --- p.58 / Chapter 3. --- Conclusion --- p.60 / Chapter 4. --- Experimental Section --- p.61 / Chapter 5. --- Reference --- p.69 / Appendix --- p.73 / NMR Spectra --- p.78

Thesis (M. Sc.)--York University, 2002. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references (leaves 83-87). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ71628.

Essen, University Diss., 2003.

This study investigated the reduction reaction of ruthenium tetroxide by various aliphatic alcohols in acidic medium. UV-Vis spectroscopy still plays an essential role in the analysis and study of volatile ruthenium tetroxide and was used in this study to collect kinetic data. This data was analyzed using graphical and computational methods, such as Mauser diagrams and kinetic simulation software. From the results obtained it is proposed that the reaction occurs by the following two-step reaction model: Ru(VIII) k1 Ru(VI) Ru(VI) k2 k-2 Ru(III) Molar extinction coefficients and conditional rate constants were calculated using kinetic simulating software and a hydride transfer mechanism was proposed. The temperature dependence of this reduction reaction was also investigated and thermodynamic parameters calculated. Ruthenium concentrations were determined using a method employing UV-Vis spectroscopy. The method proved to be a reliable, sensitive and simple technique.

M.Sc. (Chemistry) / Compounds 2-(3,5-dimethyl-1H-pyrazol-1-yl)ethyl diphenlyphosphinite (L1), 2-(3,5-di-tert-butyl-1H-pyrazol-1-yl)ethyl diphenlyphosphinite (L2), 2-(3,5-diphenyl-1H-pyrazol-1-yl)ethyl diphenylphosphinite (L3), 2-(3,5-di-tert-butyl-1H-pyrazol-1-yl)ethyl diethylphosphite (L4), 2-(3,5-di-tert-butyl-1H-pyrazol-1-yl)ethyl diethylphosphite (L5) and 2-(3,5-diphenyl-1H-pyrazol-1-yl)ethyl diethylphosphite (L6) were synthesized and characterized by 1H NMR, 31P{1H} NMR and 13C{1H} NMR spectroscopy. Reactions of L1–L6 with [Ru(p-cymene)Cl2]2 in 2:1 ratio formed six neutral complexes, [Ru(p-cymene)Cl2(L1)] (1), [Ru(p-cymene)Cl2(L2)] (2), [Ru(p-cymene)Cl2(L3)] (3), [Ru(p-cymene)Cl2(L4)] (4), [Ru(p-cymene)Cl2(L5)] (5) and [Ru(p-cymene)Cl2(L6)] (6). The neutral complexes 1–6 were converted to salts of the general formula [Ru(p-cymene)ClL]X and [NaRu(p-cymene)Cl2L]X {X = BArF- or BPh4-} (1a,1b, 2a, 2b, 3a, 4a, 4b, 5a, 5b, and 6a) by reaction of complexes 1–6 with NaBArF (BArF = 3,5-CF3(C6H3) and/or NaBPh4 in 1:1 ratio. Neutral and ruthenium complexes and their salts were characterized by a combination of 1H, 31P{1H} and 13C{1H} NMR spectroscopy, mass spectrometry, elemental analysis and in selected cases by single crystal X-ray crystallography.

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