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The current thesis presents a detailed modelling study of the selective oxidation of ethane over noble metal coated surfaces in short contact time reactors. Computational studies were performed featuring heated gas streams flowing through ceramic-foam catalysts coated with platinum and followed by a long inert section. The detailed chemical kinetic mechanisms, with coupled surface and gas-phase chemical reactions, were explored via extensive reaction path and sensitivity analyses to assess the relative contributions of the homogeneous and heterogeneous chemistries and to establish the key heterogeneous pathways driving the chemical processes. A comprehensively validated detailed chemical mechanism was used for the gas phase. The mechanism initially featured 44 chemical species and 271 reversible reactions and was later extended to 176 reactants with 993 reversible reactions. Heterogeneous models describing the surface chemistry were derived on the basis of classical kinetic collision theory and with energy barriers obtained from Density Functional Theory studies combined with the Unity Bond Index-Quadratic Exponential Potential method. The derived surface mechanisms account for differences in site occupation and surface bonding types and include four reaction classes (direct adsorption, adsorption on an adsorbate, surface reactions with adsorbed reactants and uni-molecular surface reactions including desorption) via 35 adsorbed chemical species and 284 reversible reactions. The complete chemistry was thoroughly evaluated by comparison with multiple sets of existing and new experimental data provided by industrial partners. Key modelling parameters in the process, such as streams velocities, temperature profiles, catalyst loading and pressure were critically examined. The reaction dynamics were validated with C2H6/O2/H2 mixtures with different initial hydrogen contents and with oxygen to carbon weight ratios ranging between 0.25 and 0.9. The major chemical pathways for the production of ethylene through the selective dehydrogenation of ethane, combined with the heterogeneous oxidative were identified.

Lewis base catalysis has been studied extensively in recent years as a powerful tool for introducing asymmetry into a variety of reactions, avoiding the use of expensive and potentially toxic metal catalysts. There is however still ample scope for the development of procedures for the non-enzymatic catalytic kinetic resolution (KR) of amines. Unlike alcohols, the intrinsic high reactivity of amines towards acyl and sulfonyl donors makes their KR highly challenging. As a result, there are relatively few publications on non-enzymatic catalytic KR of amines via acylation1-8 and none via sulfonylation. This thesis describes the development of a new class of chiral 2-aryl-(4-dialkylamino)pyridine-N-oxides (2-Ar-(4-DAAP)-N-oxides) (A), which are chiral by virtue of atropisomerism around the biaryl axis, and their application as catalysts for the KR of amines via sulfonylation. [molecular structure diagram] The use of C-H activation was explored for the development of a concise and modular synthetic procedure to the target catalyst structure. As a result, the key step in our final synthesis is a microwave (MW) assisted C-H halogenation procedure.(9) This reaction provides facile access to a di-ortho functionalised late stage intermediate from which a subsequent Pd catalysed cross coupling with a range of activated aryl partners provides access to an array of chiral catalyst structures. [molecular structure diagram] These catalysts were synthesised for assessment in the kinetic resolution of the axially chiral amine NOBIN, a synthetically useful chiral ligand which suffers from a difficult enantioselective synthesis. [molecular structure diagram] This thesis will provide a description of the synthetic route developed to achiral and chiral catalysts, the dependence of sulfonylation rates on the electronics of the catalyst and the key role of C-H activation in achieving a successful efficient synthesis of the target chiral catalyst structures. *For molecular structure diagrams, please see the PDF of the thesis.

The unfavourable use of metal-based catalysts in organic synthesis can be overcome by using small organic molecules; organocatalysts. Herein we report the development and synthesis of a novel range of organocatalysts derived from amino acids incorporating imidazole, thiourea and phosphoramide moieties to confer the capability to act as bifunctional organocatalysts. Our organocatalyst, a phosphoramide derived from valine, showed initial success in the catalytic allylation of aldimine with allyltrichlorosilane, producing 40% ee. Oxazoline catalysts derived from 2-pyridines have been shown to be effective activators of trichlorosilane for the reduction of ketones and ketimines. The reaction however suffered from chloride promoted ring opening of the catalyst. By replacing the oxygen of the oxazoline moiety with sulphur we were able to successfully avoid this problem. Further expansion of the substrate scope was achieved, heterocyclic imines were reduced in good enantioselectivity, up to 89% ee.