Chapter 1 introduces the phenomenon of Magnetic Chiral Anisotropy in chiral conductors and reviews the current literature on chiral charge transfer molecular conductors and synthetic routes towards them. The second part of the chapter focuses on examples of chiral anionic species reported in the literature. Chapter 2 describes the synthesis and improvements to the literature procedures for organic donor molecules: tetrathiafulvalene, tetraselenafulvalene and bis(ethylenedithio)tetraselenafulvalene. The synthesis and characterisation of new chiral TTF imine systems are also reported. A stable TTF imine derivative of chiral biphenyl amine was used in the synthesis of a homochiral bimetallic helicate with copper(I). Unusual structural and magnetic properties of this compound are reported. Chapter 3 focuses on the synthesis and properties of optically pure anionic complexes, [MIII(Ln)2]-(M = Co, Fe), of chiral pyridinecarboxamide ligands (Ln). The complexes show interesting extended structures ranging from 0D discrete units through 1D zigzag chains to 2D honeycomb layers. The complex anions were used in the synthesis of radical cation salts with tetrathiafulvalene (TTF). The salts (TTF)[CoIII(R,R-L1)2] and (TTF)[CoIII(S,S-L2)2]·EtOAc were characterised by single crystal X-ray diffraction and conductivity measurements. Solution spectroscopic and cyclic voltammetric evidence points to the formation of soluble assemblies between TTF+ and the counterion which correspond to the stoichiometry observed by crystallography and other methods in the solid state. Chapter 4 describes the synthesis of the first diastereomerically pure, organicsoluble salts of cobalt, iron and chromium complexes of optically pure chelate: H4EDDS. A number of synthetic approaches were attempted, but finally the PPh4[MIII(EDDS)]·2H2O series emerged providing readily accessible compounds in reasonable yields via the silver salts. The species are very soluble in methanol, acetonitrile and even THF and isolation of highly crystalline solids is possible upon addition of water. The structures of the three compounds are isomorphous and comprise of H2O-bridged extended hydrogen bonded structures with large channels occupied by the counterion molecules. The magnetic properties and circular dichroism spectra are reported. The diastereomeric purity in the paramagnetic systems is assessed through powder XRD. Chapter 5 focuses on the use of organic-soluble EDDS complexes in the resolution of optically active cations and as a chiral NMR shift agent. The initial results of the resolution of (±)-[RuII(bpy)3]2+ are reported along with the crystal structure of the {Λ-[RuII(bpy)3]}{Λ-[FeIII(S,S-EDDS)]}Cl·H2O adduct. The result of testing of the diamagnetic PPh4[CoIII(S,S-EDDS)] salt as·a 1H NMR shift agent for chiral complex cations: [ML3]2+, (M = Co, Ru, Fe; L = bpy, phen, en) and small organic molecules are also reported. Chapter 6 describes the electrochemical synthesis of a new family of conductive optically pure tetrathiafulvalenium and tetraselenafulvalenium salts D3[MIII(S,S-EDDS)]2·nH2O (where D = TTF, TSF; M = Co, Fe, Cr). The compounds are characterised by single crystal X-ray diffraction, conductivity measurements and elemental microanalysis and exhibit well-behaved semiconductor behaviour with conductivities up to 2.8·10-4 S·cm-1 (Ea ca 0.1 eV). Computational work indicates that it is feasible to generate metallic conductors with similar structures. Initial results for an ET analogue showing metallic conductivity are also reported. Chapter 7 details the experimental procedures used to carry out the work in this thesis.

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We investigated different strategies for the preparation of armoured polymer particles. Inorganic nanoparticles, such as clay platelets and Ludox colloidal silica grades, were used as solids-stabilisers in processes such as miniemulsion, suspension and/or emulsion polymerisations. These nanoparticles were either assembled at liquid-liquid interfaces for the stabilisation of monomer droplets or adsorbed onto solid surfaces in the case of poly(vinyl acetate) latex particles. Colloidal assembly was promoted by modifying the pH and/or the ionic strength of the dispersion medium, thereby tuning the surface properties of the nanoparticles. When prepared in miniemulsion polymerisation, latexes with controlled particle size distributions were obtained. Their diameter was dictated by the amount of solids-stabiliser (Laponite clay) or by the dimensions of the building blocks (Ludox colloidal silica). We developed a versatile emulsion polymerisation process leading to silicaarmoured poly(vinyl acetate) particles and showed that quantitative disc centrifugation analyses throughout the polymerisation process unravelled mechanistic aspects of particle formation and growth. Stability of the armoured particles was studied in dispersion and after spray-drying the hybrid dispersions. The thickness of the silica shell on the polymer particles had an important role in limiting polymer inter-diffusion upon film formation. The obtained powders were tested as additives in cement-based formulations for tile adhesives. However, desired performance characteristics were not obtained in comparison to standard formulations. Soft polymer composite foams were prepared through freeze-drying a mixture of colloids. ‘Large-soft’ particles of poly(vinyl laurate) reinforced by an armouring layer of ‘small-hard’ nanoparticles of colloidal silica led to the formation of highly porous open-cell foams. Upon addition of a third conducting colloidal component, this newly designed material proved promising results as a gas sensor.

Monodentate phosphorus ligands based on BINOL have been synthesised and applied to metal catalysed pressure hydrogenation and conjugate addition. Novel phosphorus containing enantioselective organocatalysts have been synthesised from DPEN and proline, and studied in the Michael addition of acetone to trans-β- nitrostyrenes, with up to 96 % e.e. The optimum reaction conditions for reaction rate and enantioselectivity have been investigated. Related proline-DPEN coupled organocatalysts have been synthesised and applied to the coupling reaction between DEAD and aldehydes. The proline-DPEN coupled compounds have been investigated for uses as ligands in the ruthenium catalysed asymmetric transfer hydrogenation of ketones in an aqueous medium. The hydrogenation reactions can be performed with good conversions and up to 98% e.e.

The thesis describes the development of various novel emitters for the production of gaseous ions from solutions of non-volatile, thermally labile samples for the purposes of mass spectrometry. Nano-electrospray emitters each containing two separated channels running throughout the length of the emitter were fabricated and evaluated. These emitters were made from “theta-shaped” borosilicate capillaries, employing a number of different coating procedures. Loading of different solutions into the channels demonstrated the possibility of studying solute interactions on ultrashort timescales. It is proposed that interactions took place in a shared Taylor cone. The formation of specific adducts from vancomycin and diacetyl-l-lysyld- alanyl-d-alanine was observed by mass spectrometry. From consideration of the extent of H/D exchange between vancomycin and deuterated vancomycin, it was concluded that the interaction times were of the order of 10-5 s. Underlying theoretical considerations, design and fabrication from carbon nanotubes (CNTs) of emitters for field desorption and field ionization ion sources are described and discussed. The emitters fabricated made use of arrays of vertically aligned multi-walled CNTs with in most cases an average length and radius of 15 μm and 35 nm respectively. Emitters using dense coverings of nanotubes and emitters with nanotubes selectively grown so that the height of each nanotube was twice its separation from its nearest neighbour were investigated. Characterisation of the CNTs by field electron-emission confirmed their effectiveness as field emitters. Fowler-Nordhein plots indicated fields of 6.14x109 +/- 0.72x109 V/m at a potential of 700 V. Field ionization of He, Ar, Xe, methane and acetone was achieved with these same CNTs; neither the inert gases nor methane have been field ionised with conventional activated-wire emitters. The fields generally accepted to be required for field ionisation of He and Ar are of the order of several 1010 V/m. To create emitters which would not need to be removed from vacuum between experiments, a means of injecting both liquids and gaseous samples directly to the bottom of the CNTs was devised. This involved drilling 20 μm diameter holes through the silicon substrate between intended sites of nanotube growth, but before actually growing the CNTs. It was discovered that the presence of the holes led to surface migration of the nickel catalysts initiating CNT growth. Experiments undertaken to achieve mass spectrometric measurements with the arrays of CNTs as emitters are described and discussed.

This project is divided into two parts. The first part of the project involved the investigation of fish toxins produced by Streptomyces species. Samples for fishexposure experiments were prepared from an actinomycete belonging to the S. griseus clade isolated from a site of major fish kills, as well as from the type strain, Streptomyces griseus DSM 40236. Fish-exposure samples were prepared through a series of consecutive HPLC separations. We were able to narrow down the highest level of fish toxicity to four fractions, each containing only a handful of compounds. Comparison of the metabolic profile of the most toxic fractions showed that many of the compounds were common to all of them e.g. compounds yielding ions with m/z = 213, 241, 239, 301 and 309 were present in all the fractions. Some of these compounds were purified and analysed by high resolution mass spectrometry to determine their molecular formulae. A sample preparation and purification protocol for the fish toxins has been developed in this work. It was shown that the S. griseus type strain produces ichthyotoxic metabolites in addition to the environmental strain. This is a novel and unexpected observation. The second part of the project involved structural and biosynthetic investigations of the iron-chelator and natural Angiotensin Converting Enzyme (ACE) inhibitor foroxymithine. The high structural similarity of foroxymithine to the known siderophore coelichelin and the lack of unambiguous experimental evidence in the literature to support the proposed structure of foroxymithine provided the impetus for these investigations. Foroxymithine was purified from a novel source, the culture supernatant of Streptomyces narbonensis. The gallium complex of purified foroxymithine was prepared and analysed by one- and two-dimensional high-field NMR experiments (1H, COSY, HSQC, HMBC, NOESY, TOCSY and Difference NOE), which allowed the 1H and 13C NMR signals for the complex to be assigned. Careful inspection of the 1H NMR spectrum of Ga-foroxymithine revealed two signals (a major and a minor) for several of the protons. The origin of these signals was investigated using variable temperature and 71Ga NMR experiments, and by LC-MS analyses on a homochiral stationary phase. The duplicate signals were proposed to be associated with the existence of conformational isomers of Ga-foroxymithine. The absolute stereochemistry of the four amino acid constituents of Ga-foroxymithine was determined using Marfey’s method. Authentic standards of two of the anticipated acid-hydrolysis products of Ga-foroxymithine, D- and L-N5-hydroxyornithine were chemically synthesized to facilitate the Marfey’s analysis. The results confirmed that foroxymithine contains L-N5-hydroxyornithine. Similar analysis was performed using the authentic standards of D- and L-serine and the results confirmed that foroxymithine contains L-serine. Marfey’s method was also applied to elucidate the absolute stereochemistry (previously unknown) of coelichelin. Fe-coelichelin was purified from Streptomyces coelicolor M145. Marfey’s derivatised coelichelin hydrolysate and Marfey’s derivatives of L-Thr, L-allo-Thr, D-allo-Thr were analyed. The results showed that coelichelin contains D-allo-Thr. Similarly, analyses were carried out using the Marfey’s derivatives of chemically synthesised D- and L-N5- hydroxyornithine, however the results were inconclusive. The biosynthesis of foroxymithine in S. narbonensis was also investigated. A gene fragment proposed to be within the putative foroxymithine biosynthetic gene cluster was amplified by PCR from the genomic DNA of S. narbonensis. The gene fragment was cloned into a plasmid vector and sequenced. This confirmed that it encodes part of a putative formyl transferase that could be involved in foroxymithine biosynthesis. Fosmid libraries of S. narbonensis genomic DNA were prepared. Despite exhaustive efforts, a fosmid clone containing the putative formyl transferase encoding gene fragment could not be identified via PCR based screening of the library.

The field of carbon nanotube (CNT) electrochemistry has received increasing attention from the scientific community since 1996, when the first CNT electrode displaying electrocatalytic properties was reported. However, the large majority of the field functions on the assumption that the sidewalls of CNTs, both multi-walled (MWNTs) and single-walled (SWNTs), are electrochemically inert and only edgeplane- like defects, open ends and catalytic nanoparticles (NPs) are responsible for the impressive electrochemistry observed at CNT electrodes. This thesis aims to elucidate the fundamental electrochemical properties of SWNTs. Random, highly interconnected 2D SWNT networks (either as <1% or ~ 100% surface coverage) grown using catalysed chemical vapour deposition (cCVD) on an insulating support are used throughout. Unlike other growth methods, cCVD results in clean SWNTs, without the need for further purification and with limited metal NP content. Chemical functionalisation of <1% SWNT networks indicates that the main effect of introducing defects (either as sidewall addends or open ends) is a dramatic decrease in the conductivity of the SWNT network, with repercussions on the electrochemical performance of SWNTs. Disk-shaped ultramicroelectrodes (UMEs) fabricated using pristine <1% SWNT networks shows superb electrochemistry for simple outersphere redox couples and superior characteristics over solid conventional UMEs, such as lower background currents and faster response times. Importantly, reversible cyclic voltammetry (CV) obtained under high mass transport conditions suggests that the SWNT sidewall is more electroactive than previously thought. In addition, electrochemical impedance spectroscopy (EIS) coupled with SWNT UMEs is shown to be a powerful method for determining all parameters of an electrochemical reaction in a single experiment. EIS also offers tremendous promise as a detection strategy for sensing applications. The use of a thin-layer cell (TLC) configuration, generating high mass transport rates to the SWNTs, allows for the quantitative determination of electron transfer (ET) kinetics at SWNTs. The value obtained for the rate of ET again provides strong evidence that the SWNT sidewall must be electrochemically active. While <1% SWNT networks are suitable for low concentration electrochemical detection and for the investigation of ET kinetics at SWNTs, a 100% CNT material, or CNT mat, is preferred for the detection of challenging redox molecules, such as dopamine, known to foul the surface of conventional carbon electrodes. CNT mat UMEs can be used for the electrochemical detection of dopamine at micro-molar concentrations in in-vivo mimics, with no decrease in electrode performance after extensive use, outperforming any other carbon electrode material currently available.

We have shown the use of Pickering stabilisation (the stabilisation of an interface with solid particles) in the creation of different materials. This gave us access to structures not possible in normal surfactant systems. These materials have some unique properties: For instance by using the high forces holding the Pickering particles at an oil-water-interface we can create interesting droplet morphologies. The non-spherical droplets obtained this way have potential uses in materials such as self healing composites. Additionally we developed the first Pickering miniemulsion system by using Laponite clay as the stabiliser. We went on to then demonstrate the improvements the latex can impart on the properties of pressure sensitive adhesives as well as increasing the thermal stability of the encapsulated polymer. We also created the first Pickering poly(HIPE) material and have shown that it is possible to produce structures which can be used in applications such as microfiltration. Finally the first purely Pickering emulsion polymerisation system was also designed using Ludox particles as a charged stabiliser. We could then create interesting shell morphologies by post treating the armoured latex particles.

In this thesis the use of LFMM and the application of it to problems not typical tractable within a classical framework are detailed. The parameterisation of LFMM through the AOM is shown for a number of different metal ligand complexes. The developed parameters are then used to investigate numerous problems, structures and energies of first row divalent metal complexes, energies of the water exchange pathways using model structures, investigation of the true transition states of water exchange and the selectivity for different pathways, structures and behaviour of cobalt (III) cage complexes and finally ligand exchange on mixed donor chromium (III) complexes.

This dissertation is divided into five chapters. Chapter One consists of an introduction to radical cyclisation and rearrangement reactions. Chapter Two investigates the reactions of substituted arylsulfonamides 278a-l with copper bromide and an amine ligand-TPA. This reaction involves an alkyl radical generated from the copper (I) bromide/TPA complex, which can then undergo a 1,5- ipso attack onto the sulfonamide leading to a cyclohexadienyl radical intermediate. Re-aromatisation and extrusion of sulfur dioxide leads to an amidyl radical intermediate. This can undergo either cyclisation back onto the aromatic ring to give the 6-substituted oxindole 336, or reduction from H-atom abstraction by the solvent leading to rearranged amides. A minor product identified as a 5-substituted oxindole 333 may be formed from direct radical cyclisation onto the sulfonamide followed by extrusion of sulfur dioxide. An unambiguous synthesis of 333 was obtained through the Stollé method in order to rigorously identify this product. For completion, the rearranged amide 280e was also unambiguously synthesised from known literature sources. It has been shown that the selectivity towards either rearrangement or cyclisation is dependent upon the solvent used and temperature. For example, toluene induces excellent selectivity towards cyclisation (to furnish oxindoles), while using dichloromethane (DCM) induces a greater selectivity towards rearranged amides. Chapter Three explores the effects of varying the alkyl chain length on the nitrogen atom on selectivity, while keeping both the aryl group and initiator the same. It has been shown that selectivity towards the rearrangement (or decrease in cyclisation) occurred when the alkyl chain was increased from N-butyl to N-dodecyl. In addition a similar solvent effect on selectivity was observed as discussed in Chapter 3, notably relatively more rearranged amide was produced with DCM and oxindoles with toluene. Chapter four involves investigating the copper-mediated radical cyclisation of haloamides to give oxindoles directly. The final chapter consists of the experimental.