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This thesis is centred around sequential C-C bond forming processes using oxygenated electrophiles. A major part of this research focuses on the constructive deoxygenation of 2-methoxyphenol (guaiacol), a major breakdown product of the renewable feedstock, lignin. 1,2-dielectrophiles are known to be challenging substrates for catalysis if both leaving groups are of similar reactivity, however high selectivity was observed in the palladium- catalysed Grignard cross-coupling of 2-methoxyphenyl-1H-imidazole-1-sulfonate. The previously untested Grignard cross-coupling catalyst, [PdCl₂(Xylyl-Phanephos)], was found to be highly active. A 2-benzoxazolyl functionality was shown to be an excellent directing group for the chelation-controlled nucleophilic aromatic substitution of aryl methyl ethers. However, this modified Meyers reaction is limited to aryl ethers containing an ortho-chelating group. To expand the ether scope, nickel-catalysed Grignard cross-coupling was studied. [NiCl₂(PⁿBu₃)2] showed increased activity in the Grignard cross-coupling of challenging ortho-substituted anisoles compared to the well-renowned [NiCl₂(PCy₃)2] and several Ni0 -NHC systems, with a ligand steric effect demonstrated. The success of [NiCl₂(PⁿBu₃)2] was extended to more activated methoxynaphthalene substrates, in which the lowest reported catalyst loadings (0.1-0.25 mol%) were reported. Induction periods at 0.1 mol% suggested the requirement of inorganic Lewis-acidic magnesium salts to be formed in situ before any considerable activity was observed. Further work is required to increase reaction and ether scope, but this work provides a basis for exploiting lignin- derived phenols as a framework in the synthesis of functionalised chemicals of higher value. The final results chapter concerns an alternative sequential C-C bond forming process using another oxygenated electrophile. [PdCl₂((S)-Xylyl-Phanephos)] was used to accomplish a Grignard cross-coupling of vinyl tosylate, with the product then subjected to a highly enantioselective methoxycarbonylation using the same catalyst. This lead to a concise synthesis of (S)-Flurbiprofen.

The focus of this thesis is on C-O bonds activation by transition metal atoms. Lignin is a potential alternative energy resource, but currently is an underused biomass species because of its highly branched structure. To aid in better understanding this species, the oxidative cleavage of the Cβ-O bond in an archetypal arylglycerol β-aryl ether (β–O–4 Linkage) model compound of lignin with late 3d, 4d, and 5d metals was investigated. Methoxyethane was utilized as a model molecule to study the activation of the C-O bond. Binding enthalpies (ΔHb), enthalpy formations (ΔH) and activation enthalpies (ΔH‡) have been studied at 298K to learn the energetic properties in the C-O bond cleavage in methoxyethane. Density functional theory (DFT) has become a common choice for the transition metal containing systems. It is important to select suitable functionals for the target reactions, especially for systems with degeneracies that lead to static correlation effects. A set of 26 density functionals including eight GGA, six meta-GGA, six hybrid-GGA, and six hybrid-meta-GGA were applied in order to investigate the performance of different types of density functionals for transition metal catalyzed C-O bond cleavage. A CR-CCSD(T)/aug-cc-pVTZ was used to calibrate the performance of different density functionals.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23432号 / 工博第4887号 / 新制||工||1764(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 杉野目 道紀, 教授 村上 正浩, 教授 大江 浩一 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20192号 / 理博第4277号 / 新制||理||1615(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 依光 英樹, 教授 丸岡 啓二, 講師 西村 貴洋 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

京都大学 / 新制・課程博士 / 博士(工学) / 甲第24148号 / 工博第5035号 / 新制||工||1786(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 杉野目 道紀, 教授 大江 浩一, 教授 中尾 佳亮 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

The reaction barrier and heat of formation of the various dehydrogenation reactions involved in the steam reforming of ethane is a critical concern in the applications and understanding of these reactions. Focusing on Ir-based catalyst, we report a comprehensive reaction network of dehydrogenation of ethane on Ir(100) based on extensive density functional theory calculations performed on 10 C-H bond cleavage reactions, utilizing the Vienna Ab Initio Package codes. The geometric and electronic structures of the adsorption of C2Hx species with corresponding transition-state structures is reported. We found that the C-H bond in CH3C required the most energy to activate, due to the most stable four-fold hollow adsorption site configuration. Ethane can easily dissociate to CH3CH and CH2CH2 on Ir(100) and further investigation of surface temperature dependence will contribute to the research effort in this area. By using the degree of dehydrogenation of the reactant species as a variable to correlate the C-H bond cleavage barrier as well as reaction energy. DFT studies reveal that the surface Ir(100) to a great extent promotes ethane dehydrogenation when compared to other surfaces.

No description available.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第24639号 / 工博第5145号 / 新制||工||1983(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 杉野目 道紀, 教授 中尾 佳亮, 教授 藤原 哲晶 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

The reaction between the tetrahedrane cluster RCCo3(CO)9{R = CHO (1), H (3)} and the redox-active diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3- dione (bpcd) leads to the replacement of two CO groups and formation of RCCo3(CO)7(bpcd) {R = CHO (2), H (4)}. Clusters 2 and 4 are thermally unstable and readily transform into the new P-C bond cleavage cluster 5. All three clusters 2, 4, and 5 have been isolated and fully characterized in solution by IR and 31P NMR spectroscopy. VT 31P NMR data indicate that the bpcd ligand in RCCo3(CO)7(bpcd) is fluxional at 187 K in THF. Clusters 2, 4, and 5 have been structurally characterized by X-ray diffraction analyses.