<p>The objectives of this project were to synthesize and characterise pyridine carboxamide ligands and their palladium complexes and investigate their catalytic activity in the polymerization process of phenylactylene.</p>

In recent years, the catalytic properties of finely dispersed gold particles on oxide support materials have attracted much attention. Such catalysts are active for several types of oxidation reactions, in particular low-temperature carbon monoxide oxidation. The watergas- shift (WGS) reaction and the selective oxidation of CO in the presence of hydrogen are possible applications of gold-based catalysts. In this thesis we attempted to detail the key issues relevant to the deactivation of supported gold catalysts. A new aspect of the CO oxidation deactivation mechanism was comprehensively discussed. It was found that titanate nanotube supported gold catalyst (Au/TN), prepared by deposition precipitation, deactivated due to the formation of bicarbonate species on gold-sites. Moisture prevented the formation and accumulation of these species and also promoted the reaction. The Au/TN catalyst was characterised by HRTEM, in-situ DRIFTS-Mass spectrometry, BET, etc. Titanium dioxide (TiO2) is widely used as support material for various important industrial catalysts and its modification may suite specific catalytic requirements. In this work we have confirmed that the incorporation of nitrogen (N) into TiO2 increases the concentration of oxygen ion vacancies. When tested for CO oxidation, the nitrogendoped titania supported gold catalyst, Au/TiO2-xNx, was found to be a poor and unstable catalyst compared to the pure titania supported gold catalyst, Au/TiO2. Both catalysts were characterised by XRD, Raman spectroscopy, DRS-UV visible spectroscopy, TPO, BET, HRTEM etc. New Cu-based methanol synthesis catalysts, prepared by co-precipitation and deposition precipitation, were physically mixed with _-Al2O3 and tested for the direct single-step DME synthesis from syngas. The catalysts exhibited good CO conversion and DME selectivity. The loading of gold on the methanol synthesis components of the bifunctional catalysts promoted CO conversion and the WGS reaction. In addition, Au suppressed iv methanation on the bifunctional catalysts. The catalysts were characterised by TPR, XRD, BET and XRF spectroscopy.

Thesis advisor: Amir H. Hoveyda / Chapter 1 Mechanism-Based Enhancement of Scope and Enantioselectivity for Reactions Involving a Copper-Substituted Stereogenic Carbon Center: Organoborons are important building blocks of complex natural products, functional materials, and pharmaceutically relevant compounds due to their prevalent utility in C–C and C–hetero atom bond transformations. Using a readily accessible copper catalyst, we have developed highly site- and enantioselective allylic substitution by way of a threecomponent, single-vessel, and sustainable catalytic protocol. Detailed mechanistic studies revealed valuable insights which led us to develop copper–boron and copper–hydride additions to olefins with broader substrate scope, higher efficiency, and higher enantioselectivity. In addition, the method can be applied to the synthesis of biologically active molecules such as preclamol and heliespirone A and C. Chapter 2 Versatile Homoallylic Boronates by Chemo-, SN2’-, Diastereo- and Enantioselective Catalytic Sequence of Cu–H Addition to Vinyl-B(pin)/Allylic Substitution: To achieve an efficient multicomponent reaction, high chemoselectivity between a starting material and a reagent must be accomplished during the first catalytic transformation to generate an intermediate which then selectively reacts with another substrate to furnish the product in a site-, and/or stereoselective fashion. Development and application of efficient multicomponent reactions involving allylic substitution can provide alternative solutions for difficult synthetic problems in organic chemistry. Our group has developed a sulfonate-containing chiral NHC–Cu catalyzed chemo-, SN2’-, diastereo-, and enantioselective multicomponent reaction through Cu–H addition to readily available vinyl–B(pin) followed by allylic substitution to deliver homoallylic boronates. The derived homoallylic alcohols can be used as building blocks of biologically active molecules. Chapter 3 Enantioenriched Halogen-Substituted Alkenes through NHC–Cu-Catalyzed Borylation/Dehalogenation and Their Applications: Because of their unique properties, mono- and difluoroalkenes have received attention as an important class of compounds as building blocks for fluorine-containing monomers for functional polymers and biologically active molecules in medicine and agriculture. However, reported methods to prepare enantioenriched difluoroalkenes are scarce and often require undesirable amounts of precious transition metals and very high/low temperatures. To solve these challenges, we have developed a highly efficient, regio-, and enantioselective boron allylic substitution to CF3-alkenes and other halogen-substituted olefins by using an abundant copper-based catalyst. / Thesis (PhD) — Boston College, 2017. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: Kian L. Tan / Utilization of catalytic directing groups in the regioselective hydroformylation of 1,2-disubstituted olefins and in the site-selective functionalization of 1,2-diols. Chapter One: Catalytic directing groups for the regioselective hydroformylation of allylic alcohols. Chapter Two: Scaffolding catalysis as an alternate and more practical solution to the site-selective functionalization of 1,2-diols. / Thesis (MS) — Boston College, 2011. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: James P. Morken / This dissertation aims to design and develop novel and synthetically useful catalytic enantioselective C-C bond-forming reactions that employ a newly uncovered 3,3'-reductive elimination of bis(allyl)metal species. This elementary transformation allows for new routes for the enantioselective construction of a range of important motifs found in natural products. Enantiomerically enriched Z-allylic alcohols are readily accessed through the Ni-catalyzed allylation of trans,trans-dienals. Importantly, the first example of branch- and enantioselective allyl-allyl cross-coupling is presented as well, suitable for the construction of compounds bearing tertiary and quaternary carbon centers. With the aim to broaden the application of above described transformations, this dissertation also presents the development of highly efficient and convenient methods for the syntheses of substituted and functionalized allylic boronates. / Thesis (PhD) — Boston College, 2012. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

This thesis discusses reduction and oxidation reactions catalysed by the perrhenate anion and oxidation reactions catalysed by other oxo-anions i.e. sulfate and nitrate. Chapter one introduces catalytic hydrosilylation, hydroboration, deoxydehydration and alkene epoxidation and some of their applications, with a focus on high oxidation state complexes. Chapter two describes the synthesis of a salt of perrhenate [N(hexyl)4][ReO4] which is highly soluble in organic solvents. The use of this salt as a catalyst for both the hydrosilylation and hydroboration of carbonyl compounds and carbon dioxide is discussed. Catalytic methylation of amines and anilines with carbon dioxide and hydrosilanes is also reported. Labelled carbon dioxide reactions and DFT calculations are conducted in order to understand the mechanism of carbon dioxide reduction using hydrosilanes. Chapter three outlines the synthesis of a number of alkylammonium and pyridinium perrhenate salts and their application in the deoxydehydration reaction, converting vicinal diols to alkenes. The role of the counterion is discussed with pyridinium perrhenates shown to be more effective catalysts. DFT calculations are conducted to identify the most likely pathway of the catalytic cycle. Alternative reducing agents to the triphenylphosphine initially used are also studied. Chapter four reports results of organic salts of perrhenate, sulfate and nitrate as oxidation catalysts, specifically their ability to catalyse epoxidations of alkenes. By the formation of supramolecular ion pairs (SIPs), these anions are made organic soluble which is found to significantly enhance their catalytic ability, however, the organic counterions used to form these SIPs were found to be of importance. Ionic liquids are also used for the epoxidation of alkenes. Solution studies are presented to further understanding of how these compounds interact with one another in solution. Chapter five contains experimental conditions and characterisation for compounds discussed in this work.

本文綜述了氨催化的相關背景資料。此外，本文還描述了Jørgensen-Hayashi類型的二芳基脯氨醇硅醚催化劑。 / 通過烷基化反應，二羥基化反應和鄰二醇斷裂法反應，可以合成4-羥基化的1,7-二醛70 合成出的對稱的二醛是用來作為構建具有光學活性的羥基化環己烷101a, b的一個先導物，也是用來作為測試製備的糖原氨催化劑以溫和方式進行立體選擇性的一個平臺。 / 以D-阿拉伯糖為原料，按照本課題組的以前的合成策略，合成出了含有不同芳基和2,3-O保護基的七個新的手性羥基化的糖原氨催化劑（105, 131, 134, 146, 154, 157和160）。將這些催化劑應用在不對稱的分子內的羥醛縮合反應 (aldol reaction) 中，糖原氨催化劑134 (90%，93% ee) 和157 (94%，89% ee) 顯示出非常好的催化活性。 / 羥醛縮合反應的產物 (+)-101a和 (+)-101b的絶對構型是通過與已發表的文獻中的相似反應比較確定的。 / 以D-葡萄糖為原料，按照已報導過的的合成方法，合成出了一系列的手性羥基化的烯酮，這些手性羥基化的烯酮是抗癌試劑COTC的類似物。并測試了它們對正常細胞和癌細胞的細胞毒性，以及對所得的結果進行了討論。 / In this thesis, the background information on aminocatalysis is introduced. A review regarding Jørgensen-Hayashi type diarylprolinol silyl ether catalysts is presented. / 4-hydroxylated 1,7-dial 70 was synthesized via alkylation, dihydroxylation and glycol cleavage. The symmetrical dial was prepared as a precursor to construct optically active hydroxylated cyclohexane 101a,b and as a platform to test the stereoselectivities of the prepared amine catalysts in a facile manner. / Seven new chiral hydroxylated amine catalysts (105, 131, 134, 146, 154, 157 and 160) bearing different aromatic groups and 2,3-O protecting groups were synthesized from D-arabinose following established protocol. These catalysts were applied in asymmetric intramolecular aldol reaction and amine 134 (90%, 93% ee) and 157 (94%, 89% ee) displayed positive results. / The absolute configurations of aldol adduct (+)-101a and (+)-101b were sucessfully assigned by comparing to established literature work of a similar reaction. / A series of chiral hydroxylated enones were synthesized from D-glucose as anticancer COTC analogues following established procedures. Their cytotoxicities against normal and cancer cell lines were measured and discussed [with diagram]. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wu, Ho Tong. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 129-135). / Abstracts also in Chinese.

acase@tulane.edu / In Chapter 1 an overview of the field of water reduction catalysis is given, with an introduction to the concept of photo-catalytic water splitting. A background of the current research on molecular catalysts is also described. An introduction to the project is made detailing the approach to studying the molybdenum sulfide catalysts that were synthesized, characterized, and analyzed for this work. Chapter 2 describes in detail the synthesis and characterization of all the molybdenum sulfide complexes that were made. Initially looking at [Mo3S13]2- and later synthesizing derivatives of the type [Mo3S7(S2CNR2)3]+, [Mo3S4(S2CNR2)3]+, and [Mo3S4(S2CNR2)4]0 were successful. These complexes were characterized using 1H NMR, MALDI-TOF-MS, electronic absorption, and elemental analysis. A new ligand (S2CNiBu2) was also prepared for the synthesis of [Mo3S7(S2CNiBu2)3]+ complex. Chapter 3 lists all the crystal structures that were obtained for the ligands and metal complexes in this work. Metal complexes were purified using various crystallization techniques and identified and characterized. Starting from [Mo3S7(S2CNR2)3]+ complex type, the series included R = Et, Me, iBu, and 3,5-tBu(C6H3). A unique double cluster crystal structure was obtained after photolysis of [Mo3S7(S2CNiBu2)3]+ in the photosystem. The last set of four structures was found for the complex [Mo3S4(S2CNEt2)4]. Chapter 4 describes all the electro-chemical experiments and characterizations for all the metal complexes that were studied. Using cyclic voltammetry provided a starting point for understanding the behavior of these catalysts in catalytic experiments. Spectro-electrochemistry observes changes to the complexes during reductive processes and was used to test stability of the catalysts following reduction. Lastly, bulk electrolysis was used to test the electro-catalytic capability of the [Mo3S7(S2CNR2)3]+ catalysts. It was found that electrolysis at the second reduction potential yielded the highest faradaic yield for hydrogen. Chapter 5 introduces and describes the various types of photo-systems used in the field of photo-catalysis. Initial photo-catalytic experiments showed moderate activity of the [Mo3S13]2- and improvement was observed after preparing complexes of the type [Mo3S7(S2CNR2)3]+. Combining photolysis and MALDI-TOF-MS analysis revealed a transformation from the [Mo3S7(S2CNR2)3]+ cluster to [Mo3S4(S2CNR2)3]+ cationic complexes. After synthesizing and testing [Mo3S4(S2CNR2)3]+ and [Mo3S4(S2CNR2)4]0 species, they were not as efficient at generating hydrogen. / 1 / Patricia R. Fontenot

No description available.

Soluble polymer supports that could be used in thermomorphic and latent biphasic systems have been prepared and analyzed for their potential application as supports for facilitated synthesis and catalysis. Phase selective solubilities were evaluated using polymers tagged with either visible dyes or fluorescent probes. Heptane/DMF, heptane/90% ethanol-water, heptane/ethyl acetate, heptane/ ethanol and heptane/tert-butanol solvent mixtures were all studied as examples of thermomorphic or latent biphasic systems. A range of polymers, including poly-(tert-butylstyrene) (PTBS), poly(alkylsiloxanes) (PAS), poly(dodecylvinylpyrrolidone) (PDVP), poly(didodecylvinylpyrrolidone (PDDVP), poly(isobutylene) (PIB), poly(octadecyl acrylate)s (PODA), and poly(octadecyl methacrylate)s (PODMA), were tested for hydrophobic phase selective solubility. The results of these studies were compared to prior work with polar and nonpolar poly(N-alkylacrylamide)s and polystyrene. Together with this prior work, these results have indicated that a wide range of polymers and solvent mixtures can be used for the recycling of soluble polymer-bound catalysts, reagents and sequestrants using either thermomorphic or latent biphasic separation strategies.Synthetic routes to terminally functionalized polyisobutylene oligomers, useful as supports in synthesis and catalysis, are also discussed and described. Such hydrocarbon polymers serve as highly soluble nonpolar analogs of well known poly(ethylene glycol) supports for synthesis and catalysis with the difference that the polymers are separated after a reaction by an extraction with alkane solvent. The synthesis of two polyisobutylene-supported phase transfer catalysts (PTC) are also described. These PTCs utilize the robust triazole functionality as a key synthetic step towards the preparation of the catalytic species. N alkylation of a PIB-supported triazole provides a direct route to the preparation of a PTC. Preparation of a tertiary phosphoninium salt containing a terminal alkyne allows simple attachment of the PTC to a PIB-supported azide via a triazole linker using Sharpless' Cu (I) [3 + 2] cycloaddition. These materials are active in catalyzing solid-liquid PTC and can be easily recycled by liquid-liquid extraction techniques.