Thesis (Honors)--College of William and Mary, 2009. / Includes bibliographical references. Also available via the World Wide Web.

Thesis (Ph. D.)--York University, 2000. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ59125.

Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves.

High surface area catalysts have been studied and applied in a wide range of chemical reactions and processes. The related microscopic details of surface chemistry are important and can be effectively explored employing surface science techniques. My dissertation focuses on investigations of catalytic properties of gold, primarily using vacuum molecular beam techniques, temperature programmed desorption (TPD) measurements, reflection-absorption infrared spectroscopy (RAIRS), and density functional theory (DFT) calculations. I conducted fundamental studies of hydrogenation reactions on a H atoms pre-covered Au(111) single crystal surface with co-adsorption of various chemical compounds, including acetaldehyde (CH₃CHO), acetone (CH₃COCH₃), propionaldehyde (CH₃CH₂CHO), water (H₂O), and nitrogen dioxide (NO₂). These studies allow better understanding of hydrogenative conversions facilitated by gold catalysts, which show great promise in hydrogenation applications but for which relevant fundamental studies are lacking. The experimental results unravel the unique and remarkable catalytic activity of gold in hydrogenation reactions: i) H atoms weakly absorb on the Au(111) surface and have a low desorption activation energy of ~ 28 kJ/mol; ii) acetaldehyde can be hydrogenated to ethanol at a low temperature of < 200 K; iii) propionaldehyde can be hydrogenated to 1-proponal (CH₃CH₂CH₂OH) on H pre-covered Au(111) whereas 2-propanol (CH₃CH(OH)CH₃) cannot be formed in the reaction of acetone with hydrogen atoms; iv) a coupling reaction of aldehyde-aldehyde or aldehyde-alcohol is observed on the H pre-covered Au(111) surface at temperatures lower than 200 K and this reaction can produce various ethers (symmetrical or unsymmetrical) from aldehydes and alcohols with the corresponding chain length; v) co-adsorbed H atoms have a strong interaction with water on the gold model surface and induce the dissociation of the O-H bond in water, which cannot be dissociated on the clean surface; vi) we observed a facile reaction of NO₂ reduction on H covered Au(111) and NO is produced at 77 K, yielding high NO₂ (100 %) conversion and selectivity towards NO (100 %) upon heating the surface to ~ 120 K. These studies indicate the exceptional catalytic activity of gold and enhance the understanding of surface chemistry of classical supported Au-based catalysts at the molecular scale. / text

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Selective 1,2-hydrosilylation of 1,3-dienes is a challenging problem to solve for transition metal catalysis. Butadiene, specifically, would be a useful substrate because 3-butenylsilane products have promise as superior coupling reagents for hybrid organic/inorganic materials synthesis. In this thesis, we describe the first selective 1,2-hydrosilylation of conjugated dienes, including butadiene. / Chemistry and Chemical Biology

published_or_final_version / Chemistry / Master / Master of Philosophy

published_or_final_version / Chemistry / Master / Master of Philosophy

No description available.

The hydrogenase enzyme catalytically converts protons to hydrogen. The hydrogenase enzyme contains a number of [Fe₄S₄] clusters that act as an electron transport chain, shuttling electrons to the active site. To replicate this, [FeFe]hydrogenase mimics featuring redox active quinone moieties annealed onto an Fe₂S₂(CO)₆ core were synthesized. EPR of these compounds revealed significant communication between the quinone ligand and the Fe₂S₂(CO)₆ core upon one electron reduction. Mimics featuring the redox active 2-phenylazopyridine ligand annealed onto [μ-1,3-propanedithiolato]bis(tricarbonyliron) and [μ-1,2-benzenedithiolato]bis (tricarbonyliron) were also synthesized. UV-Visible spectroscopy showed that metal to ligand charge transfer was occurring in these complexes The hydrogenase enzyme also contains a proton transport chain. [μ-1,2-Benzenedithiolato]bis(tricarbonyliron) complexes substituted with hydrogen donating phosphines were synthesized to mimic this. Attempts to synthesize the thiol substituted phosphine complex were unsuccessful, so protection group chemistry was employed. Electrochemistry of the resulting complexes showed an increase in catalytic current as well as a decrease in overpotential, when compared to the triphenylphosphine substituted complex. Finally, an effort to combine a redox active and hydrogen donating moiety into a single complex using substituted 2-phenylazopyradine moieties was attempted without success.