In this study several systems have been examined: in particular, asymmetric hydrogenation of C=C bonds and a prototypical C-C bond forming reaction. By synthesis and application of a range of chiral pyrrolidine-based sulfides, which robustly anchor to Pd nanoparticles, true heterogeneous enantioselective catalytic C=C hydrogenation has been accomplished. The behaviour and adsorption geometry of the reactant on a Pd(111) single crystal has been studied using a range of surface science techniques, allowing elucidation of the likely reaction mechanism. Investigation of four structurally related organic substrates and correlation of their reactive behaviour with the respective molecular adsorption geometries and molecular structures led to a reaction model being proposed, which correctly predicts the enantiomer observed experimentally in excess. Sonogashira coupling is one of a substantial class of C-C bond forming reactions, which are ubiquitous in synthetic organic chemistry. Despite the advantages of using heterogeneously catalyzed routes to perform such manipulations, mechanistic aspects of solid catalysts applied to such systems, especially the nature of the active species, remain both controversial and poorly understood. Reactor studies of the gold nanoparticle catalysed reaction in combination with pre- and post-reaction characterisation techniques have shown the identity of the active catalyst to be metallic Au⁰ nanoparticles. Observed particle size effects on catalysis were also seen to correlate well with the behaviour of the reactants on a Au(111) single crystal surface <i>in vacuo. </i>The selectivity enhancing effect of rare earth oxide supports has also been investigated. Overall, the insights provided by combining conventional surface science techniques with catalytic data from reactions carried out, under conditions pertinent to practical solid-liquid catalysis, pave the way for the rational design of future catalysts.

This thesis reports the development of two new concepts for stereoselective catalysis and their application in organic synthesis. Chapter 1 and 2 highlight the importance of stereoselective aldol reactions and the current limitations for the generation of (<i>E</i>)-enolates of amides. An alternative strategy for the generation of (<i>E</i>)-enol silanes <i>II </i>was proposed starting from alkynes <i>I</i>, and concept was successfully extended to an <i>anti-</i>selective aldol reaction (<i>Scheme I</i>). The scope of this novel process is detailed in chapter 3 and studies toward an asymmetric variant, including mechanistic discussions, are also described. Chapter 4 highlights the current state of the art in enantioselective catalytic olefin functionalisation reactions, particularly focusing on strategies using palladium. The potential challenges that lead to the lack of asymmetric palladium(II) chemistry developed are also outlined, and our solution of using a 14 electron palladium/ligand complex to explore this area of chemistry is discussed . In chapter 5, the design and syntheses of chiral ligands are detailed. Applications of the catalyst are investigated in chapters 6, <i>ee</i>’s up to 84% has been achieved for the Wacker-type cyclisation. Finally, tuning of the ligands is demonstrated in chapter 7.

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Pastes or gels are used in injection moulding to produce ceramic items. An important aspect is the expansion of the paste or gel from a entry of small cross-section to fill a larger cavity downstream. Flow visualisation during expansion has been performed. Non-uniform flow patterns were found and these can cause fractures, such as voids and laminations. Uniformity was favoured by a larger plate separation, a stiffer paste or gel and a decreasing divergent angle. The pressure drop can be predicted using an established flow model and gives good agreement if the expanding flow pattern is uniform. The addition of a straight channel to the outlet of a divergent die allowed the production of a uniform tape. A method for imaging the gel structure by measurement of the water distribution of gels and fired pellets has been developed using Nuclear Magnetic Resonance. This facilitated an understanding of the formation of lamination in wet gel and its effect on the structure of the final ceramic item. The structural weaknesses caused by lamination have been linked to a lower strength in a ceramic item by use of a mechanical break test. It is shown that a break if it has no further processing in the extrusion flow path can weaken the final ceramic item. Phase migration in pastes and gels has been investigated and two methods of predicting phase migration have been used. A numerical solution gives a fair prediction while a similarity solution predicts moisture ratio as a function of position and time only for an initial time period. Nuclear Magnetic Resonance images gave much greater detail of the liquid distribution than experiments based on splicing, weighing and drying. A parameter based on theory from the similarity solution has been used in a simple test to assess phase migration in paste or gel. For example the parameter can rank the phase migration rates with changing formulation, thereby optimising paste or gel formulation, to control liquid movement. Catalyst surface area and catalyst porosity have been found to be independent of processing conditions and formulation for boehmite gels.

This dissertation discusses a number of very different approaches towards generating models for biocatalysis. After a brief introduction to biocatalysis, the next two chapters detail two different approaches to generating enzyme-like systems possessing binding sites with catalytic functions. Two further chapters discuss systems designed to model the catalytic function of two very different proton transfer enzymes. A collaborative project in the catalytic antibody field is described in Chapter 2. The background to efforts towards fashioning catalytic sites for lactamisation, decarboxylation and proton transfer is presented. The syntheses of substrates required for these studies were undertaken and the results from the studies (insofar as they are available) are discussed. A second collaborative project attempting to use polymer imprinting technology to generate catalytic binding sites is described in Chapter 3. After a brief overview of the conception and aims of the project, details are given of monomer syntheses, polymerisation procedures and subsequent kinetic studies. Two systems intended for use as models for the general acid catalysis observed in lysozyme have been synthesised. The reasoning behind the designed features of the compounds is presented in the context of a brief review of lysozyme and previous models. Proton transfer from carbon acids is usually a difficult process. A number of enzymes have evolved to catalyse this difficult reaction. The design and synthesis of a model for such an enzyme is described. Detailed kinetic studies upon the new substrate revealed that the intended reaction course is not followed. It is possible that a new type of mechanism is being observed. A discussion of possible mechanistic pathways which the molecule may be following is presented with their relative merits and precedents.

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