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This thesis describes both direct and indirect C-H activation borylation processes, catalysed by several Rh-based catalyst precursors. Chapter One presents an overview of the processes investigated, namely diboration, dehydrogenative borylation, and direct C-H activation of hydrocarbon substrates, which give borylated species that are of interest to synthetic chemists. The uses of such borylated species are also highlighted. Chapter Two highlights the synthetic procedure for the synthesis of the catalyst precursor [Rh(acac)(C0E)(_2)], which can be used to prepare bis-phosphine catalyst precursors of the form [Rh(acacXP(_2))]- Although a procedure appears in the literature, it is not well cited. Also, this new procedure replaces [Tl(acac)] with [Na(acac)] and hence avoids the use of thallium salts. Chapter Three investigates the reaction of two vinyl(boronate) esters (VBEs) with Bzcat], and a wide array of catalyst precursors, which yield, among other species, the tris(boronate) esters ArCH(_2)C(Bcat)(_3) and ArCH(Bcat)CH(Bcat)(_3); the former results from the addition of both borons of the B(_2) unit to the same carbon atom, and are of interest due to their wide synthetic versatility. Chapter Four investigates the dehydrogenative borylation of alkenes using both HBpin and B2pin2, and several catalyst precursors. Most significantly, this route allows the synthesis of 1,1-disubstituted vinyl(boronate) esters that cannot be made by alkyne hydroboration. Chapter Five investigates the direct C-H activation of benzylic and aromatic hydrogens using the catalyst precursor [Rh(Cl)(N(_2))(P(^i)Pr(_3))(_2)]. This allows the functionalisation of hydrocarbon substrates, which are ubiquitous. Chapter Six investigates the stability of B-chlorocatecholborane to phosphines with the view to a boron analogue of the Heck reaction. In such a reaction, phosphmes would likely be employed on the catalyst. An understanding of the stability of the boron reagent under typical reaction conditions is needed, therefore, in order to prevent degradation of B-chlorocatecholborane, a process that is known for catecholborane.

Existing methodologies for the separation and detection of organotin species by liquid- and gas-chromatography coupled to inductively coupled plasma mass-spectrometry (ICP-MS) have been improved significantly. The LC separation of dibutyltin (DBT), triphenyltin (TPhT) and unidentified species in mussel tissue has been enhanced in terms of peak shape and resolution. GC-ICP-MS detection limits for organotin species are significantly reduced by addition of oxygen or nitrogen to the ICP-MS carrier gas. A comparison of LC-ICP-MS and GC-ICP-MS for the species-specific isotope dilution determination of tributyltin (TBT) in sediment extracts has shown that both methods deliver accurate results. However, GC-ICP-MS is significantly more sensitive (absolute detection limit of 0.03 pg TBT as Sn compared to 3 pg TBT as Sn by LC-ICP-MS) and provides superior isotope ratio measurement precision, which is linked to more reproducible peak integration and greater analyte signals by this technique. [sup]117Sn enriched DBT and TBT have been used to investigate the stability of species during extraction and the derivatisation efficiency of ethylation. The speciation of arsenic (As) has been performed using anion-exchange chromatography coupled to ICP-MS detection. Good separations have been achieved for up to seven species including monomethyl- and dimethylarsinic acid (MMA and DMA) and especially between arsenobetaine (AsB) and arsenite (As(III)). The accuracy and precision of the methods have been tested by analysis of a range of biological certified reference materials. Extraction methods for organotin and arsenic species have been developed using accelerated solvent extraction (ASE), and this technique has been assessed for the simultaneous co-extraction of Sn, As and Hg species from environmental samples. Accurate data were obtained for DBT, TBT, AsB and DMA in a certified oyster tissue, and promising results were also obtained for methylmercury. The combined extraction, separation and detection methods have been used to determine the vertical profiles of organotin and arsenic species in sediments from the Thames estuary (UK). Vp to nine organotin species were detected, with DBT being the predominant at levels ranging from [tilde] 12 - 160 ng/g (as Sn). The main As species were As(III) and As(V) at concentrations between [tilde] 160 - 4200 ng/g (as As). Methylated arsenicals were also detected throughout the core.

The evidence in support of the production of carbonium ions from triarylcarbinols under the influence of certain ionising solvents has been summarised. The concept of the "acidity function" of solutions outside the range covered by the terra "dilute aqueous solutions" has been discussed, including the acidity function, H0, introduced by Hamnett to cover the ionisation of simple Bronsted bases, and the new acidity function, J0, for the ionisation of secondary bases, as typified by the triarylcarbinols. The two methods by which J0 can be evaluated have been considered, together with the use of this acidity function for the interpretation of reaction mechanisms involving analagous ionisations for the production of reaction intermediates. The ionisation of some triarylcarbinol indicators in sulphuric acid-water mixtures has been studied, both colorimetrically and from absorption spectra data, the preparation of two new indicators being described. The influence of medium composition and of added salts on the absorption spectra of the triaryl. Carbonium ions has been studied. The acidity function J0 has been computed for the range 52-90% sulphuric acid by the stepwise indicator method. A method of determining the difference in basic strengths of two indicators whose ranges of ionisation just fail to overlap, involving the observed influence of added salts, has been postulated and used for the construction of the J0 scale. The influence of added salts has also been correlated with their influence on the velocities of nitration reactions. The discrepancies between the J0 scales obtained by the stepwise indicator method and by calculation from the H0 scale by the method of Gold and Hawes have been discussed.

Currently biomass is considered to be one of the main options to substitute the fossil fuels. Nevertheless, bioenergy is not the only alternative use for organic waste materials. In recent years, the utilisation of cellulolytic waste from industries, such as the paper industry and agriculture (in fields and in processing plants), is considered to be a good source of renewable carbon to produce chemical intermediates, such as glucose, lactic acid, ethanol and acetic acid, which can be returned to the productive chain. However, the principal obstacle in the use of this material for enzymatic degradation lies in the nature of the cellulose polymer. There are still many engineering, technological and chemistry related issues which remain to be resolved. The main objective of this study is to enable the production of glucose from the enzymatic hydrolysis of cellulose waste, arising from the waste of a recycle paper plant (paper crumb) by using Trichoderma reesei strain directly, instead of the commonly used mixture enzymes. This procedure, known as the single-step glucose production process, aims to reduce the costs associated in the use of pure enzymes and pre-treatments that are usually necessary to carry out the enzymatic degradation. The paper crumb is high in cellulose fibres (32%) with an alkaline characteristic, which carries a wide variety of impurities. This study recommends using existing knowledge with regards the enzymatic activity of the fungus and demonstrates its ability to degrade this substrate; regardless of the complex matrix linked to the cellulose polymer. Due to the nature of paper crumb a number of issues had to be solved during the development of the single-step production process. Firstly, the identification of an analytical method to monitor the enzymatic degradation of the paper crumb without interference of the inorganic compounds present in the substrate. The glucose analyser GL6 proved to be most suitable in this study. Secondly; the verification of the fungus’ ability to grow in this substrate by using PDA/Paper crumb plate, which allowed its adaptation gradually and reduced the time to produce enzymes. Finally, the evaluation of the enzymatic activity under acid and alkaline conditions was undertaken. It is demonstrated that the single-step process is feasible under acid conditions. The study also found that the fermentation time was the key parameter (up to 9 h.) to avoid the consumption of the glucose. The results show that the single-step process produces the same amount of glucose as the multi-step process (0.4 g/l), however the lower glucose production making it less economically attractive and less feasible to be expanded into an industrial scale. Nevertheless, the findings of this research contribute to establishing the basics for the optimisation of the glucose production process as an alternative for cellulose waste management. This adds economic value to the organic waste minimisation, which will lead to reduce cost in production processes.

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