Graphene oxide (GO) can provide a cost-effective route to a graphene-like material on an industrial scale, but produces an imperfect product. In order to improve the quality of the resultant graphene, unanswered questions regarding the structure and chemical reactivity of GO need to be addressed. In this thesis, chapters 1 and 2 serve to introduce the field of graphene and graphene oxide research, as well as standard characterisation techniques. Chapter 3 is concerned with investigating the validity and general applicability of a recently proposed two-component model of GO – the formation of the two components was shown to be largely independent of the oxidation protocol used in the synthesis, and additional characterisation data was presented for both base-washed graphene oxide (bwGO) and oxidation debris (OD). The removal of the OD cleans the GO, revealing its true mono-layer nature and in the process increases the C:O ratio, i.e. a deoxygenation. By contrast, treating GO with hydrazine was found to both remove the debris and reduce (cleaning and deoxygenation) the graphene-like sheets. In chapter 4, different nucleophiles were used to explore bwGO functionalisation via epoxy ring-opening reactions. Treatment of bwGO with potassium thioacetate, followed by an aqueous work-up, was shown to yield a new thiol functionalised material (GO-SH). As far as is known, this was the first reported example of using a sulfur nucleophile to ring open epoxy groups on GO. The incorporation of malononitrile groups, and the direct grafting of polymer chains to the graphene-like sheets was also demonstrated. The thiol groups on GO-SH are amendable to further chemistry and in chapter 5 this reactivity is exploited with alkylation, thiol-ene click and sultone ring-opening reactions. Au(I) and Pd(II) metallo-organic complexes were also prepared, and gold deposition experiments were carried out, demonstrating that GO-SH has a strong affinity for AuNPs. These CMGs have varying solubility and improved thermal stability. Chapter 6 concludes the work covered in this thesis, and full experimental details can be found in chapter 7.

An area of great current interest is the synthesis and characterisation of molecules possessing moving parts, with the goal that they can function as "nanoscopic machines" carrying out tasks that molecules with flxed conventional architectures cannot do. Rotaxanes and catenanes (mechanically interlocked architectures) represent one approach towards achieving these aims as their component wheels and lor threads are connected together but can still move in certain, controlled, directions. This thesis focuses on the problem that many of the reactions (clipping and capping) that lead to interlocked architectures are carried out under kinetic control and as a result if clipping or capping does not occur via an already threaded precursor, "mistakes"- non-interlocked molecules- are produced that cannot be "corrected" leading to lower yields. Chapter One gives a brief outline of the common synthetic approaches to interlocked architectures and the thermodynamically controlled routes that are now being developed to address the problems outlined above. Chapters Two and Three are concerned with probing the mechanism of hydrogen bond-assembled rotaxane formation and gaining insight into the requirements of a thermodynamically controlled synthesis of interlocked architectures. Chapter Four outlines the remarkable binding properties of the component macrocycle of a hydrogen bond-assembled catenane. Chapter Five uses the results of chapter four to synthesise a rotaxane under thermodynamic control using slippage illustrating exactly why this approach to synthesis is a poor one. Chapter Six describes the true thermodynamically controlled synthesis of hydrogen bond-assembled rotaxanes employing the results of chapter four and olefm metathesis. Chapter Seven describes an efficient synthesis of catenates using octahedral metal templates. These catenates complement structurally analogous hydrogen bond assembled catenanes as they provide a way of fixing the conformational preference of the component rings. In addition there are elements of thermodynamic control built into the synthesis.

This thesis reports an investigation of two families of potential gas hydrate inhibitor: quaternary amine carboxylates and sulphonates. Molecular dynamics simulations of the inhibitors have been performed both in liquid water and at the surface of a thin hydrate film under natural gas. Trajectories were analysed to determine inhibitor effects upon the structure of the water and the stability of the gas hydrate lattice. TIP conditions for the thin film study were determined from the calculated stability of a structure II gas hydrate under pressure. All three studies were analysed using radial distribution functions, time correlation functions, and order parameters to probe the underlying structure. To complement the computer modelling study, an experimental investigation of one of the amine sulphonates, N,N ,N-tributylammonium-l-(3-propylsulphonate), and one established inhibitor, polyvinylpyrrolidone was performed. These measured the effect of the inhibitor on nucleation time, crystal growth and morphology for both tetrahydrofuran and ethane hydrate. Results from the liquid water simulations indicate that bulk water is largely unaffected by the inhIbitors, while solvated water shows increased short- and long-range structure. Hydrate pressures were determined from the thin film simulations. A transition to a high-pressure phase was also found at around 20 kbar. These results are consistent with experimental data. Pressures in the middle of the hydrate stability zone were adopted for the subsequent inhibitor simulations. Inhibitor behaviour at the interface showed signs of relaxation of the gas hydrate water network, while for solvated water there was a contraction in the water network for the carboxylates head group. The experimental investigation revealed the amine sulphonate to be a more effective kinetic inhibitor of hydrate formation than polyvinylpyrrolidone. This was achieved by delaying nucleation, along with some growth modifying properties.

Saccharides act important roles in many biological processes as recognition molecules, signalling molecules and adhesion molecules. However, due to the complexity and diversity of oligosaccharides the direct synthetic approaches cannot fully meet the demands for all of the pure and well-defined oligosaccharides being studied in glycobiology. The efficient synthesis of glycomimetics, glycopolymers, offers an attractive route to solve this problem. Thus, the synthesis and application of glycopolymers of various architectures has been extensively investigated. Meanwhile, In order to explore the mechanism of the lectin-carbohydrate interactions and to get a better understanding of the structure-function relationship of oligosaccharides, the assays employed in studies of lectin-carbohydrate interactions become much more sophisticated and accurate with fast development of various analytical approaches. In this work, well-defined glycopolymers were prepared by the combination of CCTP and CuAAC click reactions. Alkyne-containing polymer scaffolds were synthesised by CCTP, followed by post-modification of the clickable polymer scaffolds with sugar azides. Moreover, a library of well-defined synthetic glycopolymers featuring the same macromolecular properties (architecture, polydispersity, valency, polarity, etc.) with difference only in the densities of different sugars (mannose, galactose and glucose) were employed to investigate the influence of different pendant epitopes on the interactions with a model lectin Con A by the traditional methods. Additionally, two powerful modem detection techniques QCM-D and SPR were also exploited to investigate the interactions of the lectin Con A, PNA, or DC-SIGN with a series of different glycopolymers. The diversities of binding properties contributed by different clustering parameters can make it possible to define the structures of the multivalent ligands and densities of binding epitopes for specific functions in the lectin-carbohydrate interactions. These conclusions can be employed as the springboard to develop new glycopolymeric drugs and therapeutic agents and to assess the mechanisms by which they work.

The performance capabilities of Fourier transform ion cyclotron resonance (FTICR) mass spectrometry are higher than any other type of mass spectrometer, making this technique suitable for a range of analytical applications. Here, FTICR mass spectrometry has been used for the structural analysis of polyketides and nonribosomal peptides, and in the identification of peptide binding sites of ruthenium(II) arene anticancer complexes. In both these applications, methods have been developed involving complementary tandem mass spectrometry techniques, specifically collision activated dissociation (CAD), electron induced dissociation (EID), and electron capture dissociation. In particular, CAD and EID have been shown to be effective in the structural characterisation of polyketides, with a method developed for distinguishing between two isomers of the polyketide lasalocid A. This method has been optimised and extended for application to non-ribosomal peptides enabling detailed structural information to be obtained with very high accuracy. Using CAD and ECD has enabled the identification of amino acids involved in binding ruthenium(II) complexes. Binding to phenylalanine and glutamic acid was observed in this work for the first time; coordination by histidine and methionine was also observed and is in agreement with previous work. Overall, new methods for highly accurate structural characterisation and binding site identification have been successfully designed and implemented.

This thesis focuses on expanding the scope of self-assembled polymeric nanostructures and their morphology transitions in response to a variety of applied stimuli. Chapter One gives an introduction to the main concepts and techniques used throughout the thesis. Chapter Two utilises a pH-deprotectable protected acid, incorporated into a diblock copolymer, in order to induce a morphology change in response to a change in pH. In addition, the effect of the hydrophilicity of the end group upon self-assembly is investigated. Chapter Three investigates a reversible pH-responsive system to induce a reversible vesicle to micelle morphology transition. This was achieved via the synthesis of an activated ester polymeric scaffold and the post-polymerisation introduction of backbone and end group functionality. Different end groups are investigated, along with the effect the molecular weight of the polymer has on the speed of transition. In addition, the controlled release of a hydrophilic payload is demonstrated. Chapter Four focuses on the incorporation of hydrophilic blocks, hydrophobic blocks or a combination of the two into sulfobetaine methacrylate containing polymers. The synthesis of these polymers by RAFT polymerisation is discussed and the polymers are thoroughly characterised by 1H NMR spectroscopy, SEC, SLS and multi-angle DLS. Chapter Five investigates the self-assembly and thermo-responsive behaviour of the polymers synthesised in Chapter Four. The subtle differences between the polymers and the effect of these differences on the responsive behaviour are highlighted. In addition the self-assembly of a thermo- pH- and CO2- triply-responsive triblock copolymer is discussed. Chapter Six investigates the synthesis and polymerisation behaviour of a sulfobetaine acrylate, in comparison to the sulfobetaine methacrylate observed in Chapter Four.

Chapter 1 introduces the concept of π-stacking. Different literature interpretations based on both model systems and theoretical observation are discussed. Chapter 2 describes how π-stacking interactions in a series of [ZnLn3]2+ complexes are affected by the incorporation of ring substituents by focusing on the fac:mer selectivity of these systems. The stability of Fe(II) complexes to undergo further functionalization post complexation is also investigated, in particular their ability to undergo copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition 'click' reactions. Chapter 3 focuses on the use of inter-ligand π-stacking interactions in the formation of asymmetric, bimetallic coordination complexes that we have termed triplexes metallohelices. The selectivity of these systems has been investigated by computational means. The structure has been confirmed by both solution and solid state measurement. In addition the inherent stability of these complexes to functionalization, both pre and post complexation, is also discussed. Chapter 4 focuses on the synthesis of water soluble variants of triplex metallohelices and their potential biological applications. In particular their anti-cancer properties are presented in detail. Chapter 5 details the experimental procedures used to carry out the work in this thesis.

We present a theoretical and computational study on two different processes of interest for the development of third generation solar cells: (i) electron injection in dye sensitized solar cells (DSSCs); (ii) mechanism of singlet fission (SF) in organic crystalline materials, commonly employed in organic solar cells. (i) Electron injection rates in DSSCs are computed through a combination of ab initio calculations and theoretical modeling. In particular, rates are calculated using a matrix partitioning approach, in conjunction with the propagation of Green’s functions. We are able to separate the entire dye-semiconductor surface in smaller sub-systems, whose study is less computational demanding. We prove that this approach is not only capable of simulating experimental results, but, due to its flexibility, can be used in a predictive way. We propose three possible applications of our method: a) a comparative study of different organic dyes sharing the same anchoring group; b) an investigation aimed to identify the optimal anchoring group for a DSSC dye, by screening 15 potential candidates in terms of adsorption strength on the TiO2 surface and electron injection properties; c) an extension of our approach for the study of metal-organic dyes, attaching the TiO2 surface through a variety of binding modes and with multiple anchoring groups. (ii) SF is studied focusing on the multi-excitonic (ME) intermediate, playing a pivotal role in the mechanism of the process. A model configuration interaction Hamiltonian is presented for the study of the electronic structure of a linear cluster of molecules undergoing to SF. The analysis of its electronic structure shows that different distances between the pseudo-triplets composing the ME produce energetically distinguishable states. In particular, we can separate the ME in two types: bound stabilized ME states whose pseudo-triplets are located on neighboring molecules, and unbound ME states, whose energy is almost equal to the energy of two triplets. We also demonstrate that, while singlet excitons are delocalized, ME states are localized. Dynamics of the ME←S1 radiationless decay is studied with Fermi golden rule, where a model is proposed to simulate explicitly the vibronic ME states. Effect of different choices of model parameters is studied, along with an analysis of the branching of the rates, showing that the transition occurs almost completely toward bound ME states.

This thesis is dedicated to continuous flow processes for the catalytic transformation of biofeedstocks into fine and speciality chemicals. Four processes, namely epoxidation and ethenolysis of a bio-waste triglyceride, reduction of artemisinin and etherification of dihydroartemisinin were developed under batch and flow conditions. First, an epoxidation reaction was studied using a modified WVI/PV/H2O2/PTC catalyst complex. The reaction proceeded with high selectivity to oleic epoxide (86 %) and high conversion (100 %) towards the epoxidation reaction in both, batch and flow systems. The enthalpy of epoxidation of cocoa butter was found to be mildly exothermic at -168 kJ mol-1. Space time yield, a key process parameter, in both the systems were similar. The epoxidation of cocoa butter was controlled under both batch and flow conditions by mass transfer and chemical reaction. Second, the ethenolysis of cocoa butter under batch conditions was optimised in terms of catalyst, solvent, temperature and pressure. The M11 catalyst proved to be the most active at room temperature and 2 bar ethylene pressure in THF solvent. The optimized system was transferred to a continuous membrane contactor system. A high yield of decene and 1,4-decadiene were achieved, 44.5 % in total, for a residence time of 59 min at 40 ℃ and ethylene pressure of 6 bar. Third, the stoichiometric reduction of artemisinin to dihydroartemisinin (DHA) was successfully transferred from batch to continuous flow conditions with a significant increase in productivity and an increase in selectivity. A DHA space-time-yield of up to 1.6 kg h-1 L-1 was attained, which represented a 42-fold increase in throughput compared to the conventional batch process. Finally, a highly active heterogeneous catalyst was found for the etherification of dihydroartemisinin to a pharmaceutical API artemether. Using the QuadraSil catalyst allowed us to eliminate one step in the reaction workup. A comparative Life Cycle Assessment of both reduction and etherification reactions showed advantages of the flow process over the optimized literature batch protocols. The results of the LCA highlight the significance of solvents in pharmaceutical manufacture and the advantage of flow technology, enabling small solvent inventories to be used.

Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) displays its advances in obtaining high resolving power, high mass accuracy, and coupling with many different tandem mass spectrometry (MS/MS) techniques. In this thesis, the superior performance of FTICR MS was demonstrated by several different applications. The peak separation limit of the 12 T solariX FTICR instrument was challenged by measuring the isotopic fine structures of several 17O enriched amyloid-β (Aβ) peptides (Chapter 2 and 3). A resolving power as high as 6 M was achieved at m/z 880, and peaks were assigned with mass uncertainty less than 70 ppb. The accurate measurement of 17O labelling ratio is of value for estimating atomic distances by NMR experiments. Furthermore high mass accuracy and high resolution are proved vital for the confident assignment of peaks in a polymeric mixture due to the sample complexity and coexistence of different adducts (Chapter 4). On the other hand, one or more of the MS/MS techniques, collisionally activated dissociation (CAD), electron induced dissociation (EID), electron capture dissociation (ECD), and infrared multiphoton dissociation (IRMPD), were used to characterize the structures of chlorophyll-a (Chapter 6), pheophytin-a (Chapter 7), and d-α-tocopheryl polyethylene glycol succinate (TPGS), repectively, and diagnostic fragments are useful for their structural identification in the future. IRMPD was particularly efficient in fragmenting chlorophyll-a and pheophytin-a compared to EID and CAD. Based on the fragmentation pattern of TPGS attached with two different adducts (Li+, Na+, K+, Ag+, and H+), investigating the influence of adducts in ECD and CAD processes are of benefit for understanding the fragmentation mechanisms when cation adducts are involved (Chapter 5). In an on-going project, FTICR also displays the capability to study intact proteins above 30 kDa (Chapter 8).