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The synthesis of iron and ruthenium compounds which contain either end-capped silyl units Fe-Si-Si-Fe or the linear sequence Si-Ru-Ru-Si respectively were explored. (I) (II) (III) End-capped iron species, e.g. I, were prepared using literature methods and two new related iron containing silyl species II and III were synthesised. These were prepared as model compounds for comparison with polymeric analogues. (IV) (V) Ruthenium silyl species of the type IV that maintain metal - metal bonding have been prepared. As an extension to this work inorganic polymeric species such as V were synthesised using the same preparation techniques. The polymeric compounds were difficult to characterise as they were unable to be chromatographed or crystallised therefore, all data was from crude mixtures. ...
This thesis describes a detailed ESI-MS investigation into the arylstibonic acids, organo-antimony-containing compounds that are currently of interest as anticancer reagents. Four arylstibonic acids, of nominal formula RC6H4SbO3H2 [R = p-chloro-, p-tolyl-, p-nitro- and α-naphthyl-] were synthesised, and a further eight archival samples from the National Cancer Institute Repository were obtained for use in the project. Results indicate clearly that the acids exist as polyoxometalate aggregates [H8(RSb)12O28], rather than monomeric species, in both the solid state and in acetonitrile solution, thus resolving a century-old debate concerning the nature of their molecular composition. Variations in solvent, time in solution and pH have also defined the stability of these aggregates under different conditions. Synthesis of arylstibonic acids...
This thesis describes the preparation and reactions of some cyclomanganated chalcones, dienones and aryl ketones. Investigation has previously been undertaken into the reaction of cyclomanganated chalcones and dienones with alkynes to give both pyranyl and cycloheptadienyl Mn(CO)₃ complexes. In the current study, the reaction was further investigated with a cyclomanganated dienone derived from a cyclic ketone which gave only the (pyranyl)Mn(CO)₃ complex (2-6) and not the cycloheptadienyl product as consistent with a mechanism previously proposed. Also extended in the current study was previous work involving the methylmanganese pentacarbonyl-mediated transformation of enynes to cyclopropanated bicyclic compounds and cyclopentanes bearing an exocyclic double bond. In the current study, benzylmanganese pentacarbonyl was used instead of m...
This thesis presents the studies on the multifunctional alkylation of the metalloligand [Pt₂ (μ-S)₂(PPh₃)₄] 1.1. Multifunctional organic groups which include semicarbazone and thiosemicarbazone, urea, isocyanate, guanidine, ketones and amides react with 1.1 to generate the corresponding functionalised derivatives containing thiolate ligands produced by alkylation of one or both sulfide centres. Polymers with suitable electrophilic branches also react to immobilise 1.1. By using Electrospray Ionisation Mass Spectrometry (ESI-MS) as the monitoring technique, [Pt₂ (μ-S)₂(PPh₃)₄] was employed as a productive template for structurally and chemically diverse thiolate-platinum complexes. Before this study, 1.1 was known to be one of the best building blocks for multimetallic molecules through the exceptional ligating ability of the two sulfid...
ZnO powders containing from 1-8 atom% aluminium ions were prepared from aqueous citrate-aminoalcohol-based gels calcined at 500◦C. The powders were characterized using 27Al NMR, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Solid state 27Al NMR clearly distinguished between different Al environments and was effective in determining the relative amounts of incorporation of Al dopant ions into the different Zn lattice sites in the zincite structure. A degree of control over dopant placement is demonstrated by modifying sol precursors and processing parameters, which allowed a syn- thesis protocol to be developed to optimise the doping effectiveness. Relatively minor variations in processing conditions can influence the degree and mode of Al incorporation. Thin films (ca 100 nm) were fabricated by spin-coating the Al-do...
In 1910 the first deliberately targeted search for a new chemotherapeutic agent came to fruition when Paul Ehrlich introduced Salvarsan for the treatment of syphilis. This thesis presents a detailed review of the history and literature leading up to and following on from Ehrlich’s discovery and thoroughly investigates the chemistry of Salvarsan and related species. A series of arylarsonic acids was prepared and fully characterised by electrospray mass spectrometry, NMR and X-ray crystallography for six examples. A detailed analysis of the hydrogen bonding in crystals of these molecules showed that they adopt several characteristic motifs which govern the packing in the crystals. Two of the examples containing NH2 groups crystallised as zwitterions while one NH2 containing example containing other bulky groups was is its molecular form....
This thesis investigates the status of the essential trace elements iodine and selenium in Waikato soils. Soil samples (368) representing different Soil Orders, land uses and soil depths were examined. A tetramethyl ammonium hydroxide extraction method followed by ICP-MS was validated for iodine determination. This method was suitable for total iodine determination and also gave a reliable estimate of the total selenium content of soils, based on analysis of Certified Reference Materials. Acid extraction of selenium was unsuitable because of difficulties with recoveries and interferences in the ICP-MS, although the use of methane and DRC-ICP-MS reduced interferences. Time and equipment constraints limited the complete validation using acid extraction for total selenium determination. Waikato soils had a mean iodine content of 20.9 mg k...
This thesis describes the incorporation of carbohydrate groups in thiourea, 1, or iminophosphorane, 2, ligands. Several carbohydrate acyl thioureas, 3, were synthesised from the reaction of protected and unprotected D‐glucosamine with acyl isothiocyanates, RCONCS. Internal hydrogen‐bonding forms a planar six‐membered ring, which locks the thiourea into an Z,E,Z‐anti conformation as shown by 1H NMR spectroscopy and confirmed by X‐ray structure determination of two examples. As neutral ligands to Rh(III), Rh(I), Ru(II), Pd(II), Pt(II) and Au(I) they bond through the sulfur atom with retention of the six‐membered ring and the Z,E,Z‐anti conformation. This was confirmed by two X‐ray structure determinations on Rh(III) and Pd(II) examples which also showed the new hydrogen‐bond formed by HN2 to a halide on the metal. Deprotonation of the l...
New hydrides of heavier p-block main group elements with a ferrocenylalkyl moiety, Fc(CH???)nEHm (Fc = (CpFeC???H???-); E = P, As, Si, Ge or Se; n = 1, 2, 4, 6 or 11; m = 1, 2 or 3) and FcCH???P(R)H (R = CH???, C???H?????? or p-CH???C???H???NO???), have been synthesised and characterised. Although some precursors of the desired hydrides, i.e. Fc(Cl)C=C(SnCl???)H and (FcCH???Te)???, which are also new compounds, could be prepared, the syntheses of the corresponding desired hydrides, FcCH???EHn, were unsuccessful probably due to their extreme instabilities. Some related primary phosphanes, [CpFeC???H???(CH???OH)(CH???PH???)], RcCH???PH??? and Fc(CH???)???PH??????BH???, phosphane oxide, FcCH???P(O)H???, and phosphinic acid, FcCH???P(O)(OH)H, were also synthesised and reported. The X-ray crystal structures of Fc(CH???)???PH??????BH3 and Fc...
The crystal structure of [Et4N][CoFe3 (CO) 13] has been determined, and shown to contain an anion with the CO ligands adopting a very different arrangement about the tetrahedral CoFe3 core to that found for the same anion, reported previously for the PPN+ salt. The relationship between the two structures can be understood in terms of Johnson's Ligand Polyhedral Model. In contrast the anion in [Et4N][CoRu3 (CO) 13] has the same geometry as that described in the corresponding PPN+ salt.
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