Thesis (M. Sc.)--Carleton University, 2001. / Includes bibliographical references (p. 83-86). Also available in electronic format on the Internet.

Thesis (Ph.D.)--University of Hong Kong, 2003. / Also available in print.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Also available online.

M.Sc. / In this study, the pyrazolyl-based ligands were synthesised and used in the synthesise of new ruthenium pyrazolyl-based complexes. The ruthenium pyrazolyl-based complex 2.4 was tested as a catalyst for the self-metathesis reaction of 1-octene. The N^N ligands: 2-(3,5-dimethylpyrazol-1-ylmethyl)pyridine (L1) and 4-(3,5- dimethylpyrazol-1-ylmethyl)pyridine (L2) were prepared from the reaction of 2- picolyl chloride (for L1) and 4-(bromomethyl)pyridine (for L2) with 3,5- dimethylpyrazole. Reactions of L1 and L2 with [RuCl2(PPh3)3] and [RuCl3·3H2O] produced [2-(3,5-dimethyl-pyrazol-1-ylmethyl)pyridine) dichlorotriphenylphosphine]ruthenium (2.1) and bis[4-(3,5-dimethylpyrazol-1- ylmethyl)pyridine-trichloride]ruthenium (2.3), respectively. The N^O ligands: 2- (3,5-dimethylpyrazol-1-yl)ethanol (L3), 2-(3,5-diphenylpyrazol-1-yl)ethanol (L4), were prepared from the reaction of 2-hydroxyethylhydrazine (for L3) and dibenzoylmethane (for L4) with 2-hydroxyethylhydrazine. Reaction of L3 with (3-phenylindenylidene)dichlorobis-(triphenylphosphine)ruthenium produced [3-phenylindenylidene-(3,5-dimethylpyrazol-1-yl)-ethanolate chlorotriphenylphosphine]ruthenium (2.4). Ligands, 2-(3,5-dimethylpyrazol-1-ylmethyl)-phenol (L5) and bis(3,5- dimethylpyrazol-1-yl)acetic acid (L6), were prepared from the reaction of o-(α- bromo-methyl) phenyl methanesulfonate (for L5) and dibromoacetic acid (for L6) with 3,5-dimethylpyrazole. Reaction of L6 with [RuCl2(PPh3)3] produced bis-[(3,5-dimethylpyrazol-1-yl)-acetic-acid-chloro(bistriphenylphosphine)] ruthenium (2.6). The C^N ligands: 1-[2-(3,5,-dimethylpyrazol-1-yl)-ethyl]-3- methyl-3H-imidazol-1-ium bromide (L7) and 1-[2-(3,5,-dimethylpyrazol-1-yl)- ethyl]-3-methyl-3H-imidazol-1-ium bromide (L8) were prepared from the reaction of 1-(2-bromoethyl)-3,5-dimethyl-1H-pyrazole (for L7) and 1-(2- bromoethyl)-1H-pyrazole (for L8) with 1-methylimidazole. Reactions of L7 and L8 with silver(I) oxide (Ag2O) produced 3,5-dimethyl-1-[2-(3-methyl-2,3- dihydro-imidazol-1-yl)-ethyl-1H-pyrazole]silver bromide (2.7) and 1-[2-(3- methyl-2,3-dihydro-imidazol-1-yl)-ethyl-1H-pyrazole]silver bromide (2.8), respectively. Reactions of silver complexes (2.7) and (2.8), respectively, with [RuCl2(PPh3)3] produced 3,5-dimethyl-1-[2-(3-methyl-2,3-dihydro-imidazol-1- yl)-ethyl-1H-pyrazole-dichloro(triphenylphosphine)]ruthenium (2.9) and 1-[2- (3-methyl-2,3-dihydro-imidazol-1-yl)-ethyl-1H-pyrazoledichloro (triphenylphosphine)]ruthenium (2.10). The synthesised complexes were obtained in moderate to low yields and were characterised by 1H, 13C{1H}, 31P{1H} NMR, IR spectroscopy, mass spectrometry, elemental analyses and ligand L5 was also characterised by X-ray crystallography. Complex 2.4 was screened for self-metathesis reaction of 1-octene. Initial run from 30-90 oC showed no activity for 1-octene metathesis below 105 oC. At 105 oC small amounts of 7-tetradecene was obtained, indicating that metathesis reaction occurs at very high temperatures (105 oC). Thermal stability test of complex 2.4, showed that rearrangement in the proposed structure of complex 2.4 occurs after heating at 90 oC for 16 h, this was evident by the 31P{1H} NMR spectrum of complex 2.4 obtained as a singlet at 28.9 ppm (after being heated), (complex 2.4 appears at 30.0 ppm before heating). From the 31P{1H} NMR study, it could be proposed, that the pyrazole arm of the ligand dissociates thus influencing the environment of the phosphorus (of the triphenylphosphine), and therefore a shift in the peaks is observed.

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.

No description available.

The chemistry of homogeneous transition metal systems offer parallels to the reactions on the surfaces of industrial hydrodesulphurization catalysts. The reactions of several ruthenium complexes with sulphur-containing reagents are described, with an emphasis on the kinetics and mechanisms thereof. The complex Ru(CO)₂(PPh₃)₃ (2), for example, reacts quickly with thiols and disulphides, producing cct-RuH(SR)(CO)₂(PPh₃)₂ (9) and cct-Ru(SR)₂(CO)₂(PPh₃)₂ (14), respectively, although 2 fails to react with unstrained thioethers. Reactions of the related complex Ru(CO)₂(PPh₃)(dpm) (dpm=Ph₂PCH₂PPh₂) are complicated by the lability of all of the three different ligands. The two dihydrides cct-RuH₂(CO)₂(PPh₃)₂ (3) and RuH₂(dpm)₂, as a cis/trans mixture (7), react with thiols to produce the hydrido-thiolato complexes 9 and RuH(SR)(dpm)₂ (13). respectively. The mechanisms appear to depend on the basicity of the hydride ligands; the more basic dihydride, 7, is probably protonated by the thiol, giving an unobserved molecular hydrogen intermediate, while 3 reacts by slow reductive elimination of H₂. The same rate constant, rate law, and activation parameters are found for the reaction of 3 with thiols, CO or PPh₃. The reaction of 3 with RSSR produces mostly 9, with small amounts of 14. The complete characterization of several members of the series 9 and 14 is described, including the crystal structure of the p-thiocresolate example of each. The reactions of 9 with other thiols, P(C₆H₄pCH₃)₃, CO, RSSR, HCl, PPh₃, and H₂, are also reported. The first three of these reactions share the same rate law and rate constant, the common rate determining step probably being initial loss of PPh₃. Some equilibrium constants for the exchange reactions of 9d (R=CH₂CH₃) with other thiols were tetermined, the Keq values increasing with the acidity of the incoming thiol. The mercapto hydrogens of 9a and 14a (R=H) exchange with the acidic deuterons of added CD₃OD. The hydridic and ortho-phenyl hydrogens exchange more slowly, presumably by intramolecular processes. Complex 14b (R=C₆H₄pCH₃) is unstable in the presence of light, exchanges phosphines rapidly with added P(C₆H₄pCH₃)₃, exchanges thiolate groups with added thiols, and is converted by high pressures of H₂ to a mixture of 9b and 3. Intermediates proposed for the mechanism of the thiol exchange reactions of 9 and 14 contain two or three thiolate groups sharing a proton. A related complex, [Ru(CO)₂(PPh₃)(μSEt)₂(μ₃SEt)Na(THF)]₂, which contains three thiolate groups on a ruthenium centre sharing a sodium cation, was isolated from the reaction of cct-RuCl₂(CO)₂(PPh₃)₂ with sodium ethanethiolate. In acetone, 9b and 14b can be formed cleanly from cct-RuHCl(CO)₂(PPh₃)₂ and cct-RuCl₂(CO)₂(PPh₃)₂, respectively, by reaction with p-thiocresolate. Complex 3 or cheaper analogues could be used as catalysts for the reduction of disulphides by H₂, or as recyclable reagents for the non-oxidative extraction of thiols from thiol-containing mixtures such as oil fractions. The chemistry described above will help to guide future researchers to systems that more closely parallel the processes occurring on the surfaces of industrial hydrodesulphurization catalysts. / Science, Faculty of / Chemistry, Department of / Graduate

M.Sc. (Chemistry) / The main aim of this study was to use pyrazolyl-based bi-and tri-dentate ligands in the synthesis of several p-cymene-ruthenium complexes. These ruthenium complexes and their corresponding ligands were subsequently tested for their anticancer and antimalarial activities...

Orientador: Dora Maria Grassi Kassisse / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T22:17:00Z (GMT). No. of bitstreams: 1 Conceicao-Vertamatti_AnaGabriela_M.pdf: 7309475 bytes, checksum: 5e1d39b92988f9d6403190c0681c65b0 (MD5) Previous issue date: 2012 / Resumo: Por apresentar basicamente fórmulas, o resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Not informed / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular