Dissertations / Theses: 'Phosphorus compounds'

1

Root, A. "NMR of phosphorus containing compounds." Thesis, University of East Anglia, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372798.

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2

Crowe, Lindsey Alexandra. "NMR of solid phosphorus-containing compounds." Thesis, Durham University, 1999. http://etheses.dur.ac.uk/4502/.

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Solid-state NMR techniques have been applied to the structure and dynamic characterisation of a range of phosphorus-containing compounds. Comparisons have been made within several series of compounds as well as studies of individual molecules with interesting NMR properties, whether dynamic, structural or magnetic. Spectral features such as shielding anisotropy, the high sensitivity of phosphorus and its large chemical shift range are extensively utilised in this work. Triple-channel, fluorine-observe and variable-temperature spectrometer facilities at different magnetic field strengths have been explored to give as much complementary information as possible. For both chlorinated and fluorinated diazadiphosphetidines, motional properties have been examined and the indirect spin-spin and dipolar interactions, together with shielding have been studied. Spectra from the NMR-active nuclei in these cyclic dimers have been used to compare effects of differing substituents on NMR properties. The bowl-shaped' molecules, calix[4] resorcinols with phosphorus functionality modifying the upper rim, constitute the other major group of compounds studied. These are of interest in inclusion chemistry. As well as simple one-dimensional NMR characterisation of solid-state calix[4]resorcinol compounds, interesting two-dimensional correlation results have helped with the assignment and conformational conclusions. A qualitative and quantitative study of a co-crystal of triphenylphosphine oxide and phenol was made to establish the nature of the disorder observed, but undefined, in an X-ray structural investigation of the hydrogen-bonded network. Complementary NMR techniques were used to extend the temperature range over which the rate of any motion can be characterised. Bandshape analysis, Tip measurement and selective polarisation inversion experiments have proved to be accurate in different regions of a variable temperature study. Other compounds explored were those which showed interesting solid-state NMR results, for example, the complexities of cross-polarisation dynamics between two abundant spins in inorganic phosphates, and compounds with potential solid-state applications. These include (i) phosphorus-containing compounds with chlorine and fluorinated aromatic substituents and (ii) complexes with transition metals. Comparison with single-crystal and powder X-ray diffraction has also been exploited. In some cases, data have been produced, and in others the applicability of a theoretical approach has led to other conclusions.

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Simpson, Bryan Garth. "Reactions of heterocycles with phosphorus compounds." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329647.

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4

Soltani, Morteza. "Strength, fracture morphology, and polymorphic phase transformations in phosphate-bonded high-alumina refractory compositions." Diss., Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/19060.

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5

Williams, Gareth Rhys. "The synthesis and applications of new organo-phosphorus and organofluorine-phosphorus compounds." Thesis, University of Manchester, 2005. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528265.

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6

Merwin, Lawrence Hale. "NMR of solid phosphorus and nitrogen compounds." Thesis, Durham University, 1987. http://etheses.dur.ac.uk/1683/.

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7

Dhaher, S. M. "Sterically hindered organo-phosphorus and -tin compounds." Thesis, University of Sussex, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374457.

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8

Clark, Lauren Lisa. "Composition and cycling of marine organic phosphorus /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

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9

Sun, Chaode. "Syntheses and reactivities of [pi]-electron rich phosphorus-nitrogen and sulfur-nitrogen ligands." HKBU Institutional Repository, 1999. http://repository.hkbu.edu.hk/etd_ra/140.

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10

Mcguire, Janine Gale. "Synthesis and properties of potentially liquid crystalline phosphorus compounds." Thesis, University of Central Lancashire, 2000. http://clok.uclan.ac.uk/20138/.

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Traditionally it was considered necessary for molecules to be either rod or disc shaped to fulfil the requirements necessary for liquid crystalline phase formation. However, recent moves away from these traditional theories have led to the discovery of molecules possessing geometries such as tetrahedral and even octahedral producing mesogenic phases. One molecular geometry not yet shown to display liquid crystalline behaviour is trigonal pyramidal. Group V elements exhibit such geometry. This thesis reports the synthesis of a number of novel phosphorus(IIl) molecules and an investigation into their possible liquid crystalline phase behaviour. Trigonal pyramidal phosphines together with the corresponding tetrahedral phosphine oxides, with three alkoxybiphenyl groups attached to a central phosphorus atom, were synthesised with varying alkyl chain lengths between C1-C22. Investigation into liquid crystalline behaviour by both sets of compounds failed to demonstrate any mesophase formation. However, tri(nonyloxybiphenyl)phosphine oxide did show evidence of crystal to crystal transitions, often seen as a precursor to liquid crystaffine behaviour. Conversion of the phosphorus molecules into a more traditional linear shape by the replacement of an alkoxybiphenyl group with a smaller alkyl or phenyl group was also undertaken to investigate possible liquid crystalline behaviour, although none was observed. Attempts were also made to extend the length of the groups attached to the phosphorus atom to a tri-phenyl ring system incorporating an azo linking unit, which has often been shown to demonstrate mesophase behaviour. This led to the synthesis of a new series of compounds, phenyl (4-alkoxyphenylazo)benzoates, which demonstrated both nematic and smectic C liquid crystalline phases. Unfortunately, synthesis of the desired phosphorus was not achieved. Di(alkoxybiphenyl)phosphine oxides separated by an alkyl spacer group, were synthesised in an attempt to produce H-shaped molecules, an arrangement that would be intermediate between rod and disc shaped molecules. Again, liquid crystalline behaviour was not observed. A series of mixed butyl and methyl phosphonium nonadecafluorodecanoates were shown to produce lyotropic liquid crystalline phases in accordance with those observed for the equivalent ammonium compounds.

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11

Kendall, Nigel Lincoln. "Nuclear magnetic resonance study of new polycyclic phosphorus compounds." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481631.

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12

Cherryman, Julian Christopher. "Solid-state NMR of tin, lithium and phosphorus compounds." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4667/.

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NMR spectroscopy is a powerful technique that allows the study of short-range electronic effects and local structure. The aim of the work has been to separate and manipulate the many different interactions so that they can be individually measured. For this we have used multinuclear techniques and probes. We have measured a range of spectra for different organotin, iminophosphorane and lithium compounds. We have obtained a selection of spectra including (^19(F {(^1)H} and doubly-decoupled (^119)Sn {(^1)H, (^19)F} for the organotin fluorides (^n)Bu(_3)SnF, Mes(_3)SnF, SnF(_2), Me(_2)SnF(_2), and (^n)Bu(_2)SnF(_2). These have been used to calculate the effective shielding anisotropies, asymmetries, effective dipolar coupling (D'), and the anisotropy in the indirect coupling (∆J), using analyses of the spinning-sideband manifolds. Simulation programs have been written to simultaneously fit multiple sets of data, which reduce the fitting errors and give the relative orientations of the tensor interactions. The (^19)F chemical shifts, indirect coupling (^1)j(SnF) and (^1)∆J(SnF) data have been summarised. For (^n)Bu(_2)SnF(_2), a structure has been proposed based on comparisons with the NMR results from the other compounds. For the iminophosphoranes, the dipolar tensor and its orientation can be measured from the (^31)P static spectrum, whilst in the MAS spectrum residual dipolar coupling lineshapes are visible. These give information about the electric dipole nature of the P-N bond and the nature of its bonding. For the lithium nuclei, the quadrupolar interaction is small, but can be directly studied. With the two NMR-active isotopes both tire shielding and quadrupolar interactions can be measured. Ab initio calculations have been used to calculate certain NMR parameters such as the shielding, quadrupolar and indirect coupling tensors from the molecular structure. Experimental data have been compared against tlie calculations to verify the accuracy of the model. At present, there is good agreement between experimental and calculated results for (^6,7)Li, (^13)C, (^14,15)N and (^31)P, though (^119)Sn remains a challenge.

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13

Locke, Ian Wyn. "Preparation and computational study of novel fullerene intercalation compounds." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299956.

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14

Cui, Jian. "Synthesis and characterization of new boron-nitrogen and boron-nitrogen-phosphorus systems." [Fort Worth, Tex.] : Texas Christian University, 2009. http://etd.tcu.edu/etdfiles/available/etd-03162010-123538/unrestricted/Cui.pdf.

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15

Ahlgren, Joakim. "Organic Phosphorus Compounds in Aquatic Sediments : Analysis, Abundance and Effects." Doctoral thesis, Uppsala University, Analytical Chemistry, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6701.

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Phosphorus (P) is often the limiting nutrient in lacustrine and brackish eco-systems, and enhanced input of P into an aquatic system might therefore negatively impact the environment. Because modern waste water manage-ment have reduced external P input to surface waters, internal P loading from the sediment has become one of the main P sources to aquatic ecosys-tems, in which relatively unknown organic P compounds seem to be more active in P recycling than previously thought.

This thesis focus is on improving analysis methods for organic P com-pounds in lacustrine and brackish sediments, as well as determining which of these compounds might be degraded, mobilized and subsequently recycled to the water column and on what temporal scale this occur. In both lacustrine and brackish environments, the most labile P compound was pyrophosphate, followed by different phosphate diesters. Phosphate monoesters were the least labile organic P compounds and degraded the slowest with sediment depth. In regulated lakes, it was shown that pyrophosphate and polyphos-phate compound groups were most related to lake trophic status, thus indi-cating their involvement in P cycling. This thesis also indicates faster P turn-over in sediment from the brackish environment compared to sediment from the lacustrine environment.

A comparison of organic P extraction procedures showed that pre-extraction with EDTA, and NaOH as main extractant, was most efficient for total P extraction. Using buffered sodium dithionite (BD) as a pre-extractant and NaOH as main extractant was most efficient for extracting the presuma-bly most labile organic P compound groups, pyrophosphate and polyphos-phate. Furthermore, it was determined that organic P compounds associated with humic substances were more recalcitrant than other P compounds, that the BD step used in traditional P fractionation might extract phosphate monoesters, and that NMR is a statistically valid method for quantification of organic P compounds in sediment extracts.

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16

Francis, M. D. "Studies of low co-ordinate phosphorus, arsenic and antimony compounds." Thesis, Swansea University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637005.

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The work described in this thesis revolves around one main theme: the chemistry of the group 15 elements phosphorus, arsenic and antimony in low co-ordinate states. The work is divided into seven chapters. Chapter one is a general introduction and briefly reviews the basic properties of the group 15 elements. It also introduces the double bond rule, the concept of low co-ordination and how low co-ordinate main group species can be stabilised using bulky substituents and/or delocalisation of electrons. Chapter two describes the synthesis and characterisation of a group 15 substituted cyclopentadienyl system, namely the 1,4,2-diphosphastibolyl anion [1,4,2-P₂SbC₂Bu^t₂]^- which contains two di-co-ordinate phosphorus centres and a two co-ordinate antimony centre. Chapter three describes the preparation and characterisation of a range of transition metal complexes derived from the diphosphastibolyl ring anion in which it exhibits η⁵:η¹ co-ordination behaviour. The theme of Chapter four is the synthesis and characterisation of main group compounds derived from the diphosphastibolyl anion including a polyhetero-plumbocene and-stannocene. Chapter 5 moves away from the area of substituted cyclopentadienyl systems and into the field of group 15 heteroalkynes. The first part describes the synthesis and characterisation of a compound formulated as a rare example of a σ-phosphaalkyne complex in which the phosphaalkyne bonds to a ruthenium (0) centre via its lone pair of electrons. The second part discusses the coupling reaction of phosphaalkynes with an alkyne at a dirhodium centre. The co-ordination properties of the coupled products are investigated. The latter part of Chapter 5 describes the synthesis and characterisation of compounds derived from the metal mediated coupling reactions of the arsaalkyne, As≈CMes^*. These compounds are only the second and third reported to be derived from the direct reaction of an arsaalkyne. Chapter 6 discusses the 1,2-addition reactions of phenylselenyl halides to phosphaalkynes. The factors influencing the regio- and stereochemistry of the resulting selenophosphaalkenes are considered and a possible mechanism for the process is proposed. The final chapter contains some concluding remarks on the work.

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17

McIntosh, Alan Paton. "Reaction of phosphorus containing compounds with transition metal multiple bonds." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/30483.

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18

Kyriacou, Panos. "Structure and synthesis of some phosphorus compounds of potential biological activity." Master's thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/15895.

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19

Bravo-Altamirano, Karla. "New methodologies for the preparation of organophosphorus compounds via carbon-phosphorus bond formation." Fort Worth, Tex. : Texas Christian University, 2007. http://etd.tcu.edu/etdfiles/available/etd-04252007-115357/unrestricted/bravo.pdf.

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20

Khan, Rana. "Structural studies of halogen, interhalogen and pseudohalogen compounds of phosphorus, selenium and tellurium." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/structural-studies-of-halogen-interhalogen-and-pseudohalogen-compounds-of-phosphorus-selenium-and-tellurium(b1ba6ec9-198c-4de5-be73-f136a4db3ee0).html.

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A series of compounds with the general formula R3PX2 and R3PX4 (where R = o-tolyl, m-tolyl, p-tolyl, o-anisyl, m-anisyl, p-anisyl, o-thioanisyl, p-thioanisyl, p-fluorophenyl, p-chlorophenyl, mesityl and X = Cl, Br, I) have been synthesised and studied by X-ray crystallography, multinuclear NMR spectroscopy and Raman spectroscopy. A study of the conformational features of the aryl groups in these structures was undertaken in order to investigate the role of steric effects and crystal packing on P-X and X-X bond lengths. Compounds with the general formula RSeX / RSeX3 (where R = p-fluorophenyl, p-chlorophenyl, p-bromophenyl, p-iodophenyl and X = Cl, Br, I) have been synthesised by reacting the diselenides with halogens in the stoichiometric ratios. The X-ray crystal structure of p-ClC₆H₄SeI.I₂ is the first crystallographically characterised example of a compound of stoichiometry RSeI₃, although it is better represented as an I₂ adduct of a Se(II) iodide than a Se(IV) compound. In contrast, (p-FC₆H₄)Se-Se(I)₂(p-FC₆H₄) is an I₂ adduct where the Se-Se bond has not been cleaved by iodine. Both structures are stabilised by weak Se...I and I...I interactions. p-FC₆H₄SeCl₃ is an example of a dimeric structure with bridging chlorines. [Ph₄PX] and Ph₃PX₂ were reacted with PhEX (where E = Se, Te and X = I, Br, Cl) to produce salts containing [PhEX₂]- and [PhEX₄] anions. Where possible all the products were then analysed via NMR and Raman spectroscopy and X-ray crystallography. The reactions of the ligand tris-p-fluorophenyl phosphine with sulfur and selenium are presented along with the subsequent reactions of these compounds with diiodine. All of the compounds are characterised via X-ray crystallography.

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21

Banks, Mavis. "Flame retardation of polymers by chemical modification with phosphorus-containing compounds." Thesis, Lancaster University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316073.

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22

Robbie, Alasdair J. "The study of transition metal complexes of phosphorus-nitrogen containing compounds." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433327.

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23

Stchedroff, Marc. "Studies on ruthenium and osmium clusters containing phosphorus and nitrogen compounds." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311947.

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24

Lin, Yi-Chun Ph D. Massachusetts Institute of Technology. "Bond activation and catalysis by nontrigonal tricoordinate and tetracoordinate phosphorus compounds." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113980.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 2017.
Cataloged from PDF version of thesis. Vita.
Includes bibliographical references.
Molecular distortion has a profound impact on the electronic structure and reactivity of molecules. This dissertation describes studies on E-H bond activation and catalytic reactivity of [sigma]³- and [sigma]⁴ -phosphorus compounds with distorted nontrigonal structures. Specifically, a rare example of N-H oxidative addition to a planar, C2v-symmetric P(III) center is described in Chapter 2. The kinetics and computational studies implicate a noncanonical, phosphorus-based electrophilic pathway for this transformation. As detailed in Chapter 3, a Cs-symmetric phosphorous triamide and its P-N cooperative reactivity are presented. B-H activation and catalytic imine hydroboration are achieved via the combination of the electrophilic phosphorus center and the basic anilide ligand moiety of this Cs-symmetric phosphorus compound. Finally, Chapter 4 extends the study of distorted phosphorus compounds to [sigma]⁴ -phosphorus molecules. Iminophosphoranes bearing constrained ligand platforms are synthesized and their distortion-induced B-H, B-O and Si-H bond activation reactivity are presented. This research provides insight into the influence of molecular symmetry on the reactivity of [sigma]³- and [sigma]⁴-phosphorus compounds and represents an initial step toward the discovery of new chemistry in other distorted phosphorus molecules.
by Yi-Chun Lin.
Ph. D.

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25

Ito, Kenji. "Kinetic Study on Single-Electron Transfer Process from Trivalent Phosphorus Compounds." 京都大学 (Kyoto University), 2002. http://hdl.handle.net/2433/149545.

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26

Holliday, Mitchel. "A comprehensive study of phosphorus additives in foods and their effect on the American population." Menomonie, WI : University of Wisconsin--Stout, 2007. http://www.uwstout.edu/lib/thesis/2007/2007hollidaym.pdf.

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27

Zhu, Shuguang. "Generation of 1,3-dipoles containing carbon, nitrogen, sulphur and phosphorus." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0008/NQ34250.pdf.

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28

Nordheider, Andreas. "Phosphorus-tellurium heterocycles and their lighter chalcogen analogues : from small rings to macrocycles." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/5546.

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The research on phosphorus-chalcogen compounds enjoys a long tradition in the field of inorganic chemistry, which has led to applications such as strike-anywhere matches, precursors for metal chalcogenide thin films and versatile reagents in organic synthesis. Whereas a wide range of phosphorus-sulfur and -selenium systems is known, the literature lacks information about compounds incorporating phosphorus-tellurium bonds. This thesis describes fundamental studies that develop the basic understanding of the synthesis of phosphorus-tellurium systems and the structural characteristics of these species. The focus will be on cyclic structural motifs as these offer novel bonding modes and often an interesting reactivity. In addition, the novel compounds are compared with the properties of the sulfur and selenium analogues. Three different approaches were developed to stabilise and study compounds incorporating phosphorus-tellurium bonds: a) Stabilisation of binary organophosphorus-tellurium heterocycles by bulky substituents, b) the utilisation of P₂N₂ rings based on the dianions [{EP(NtBu)(μ-NtBu)}₂]²⁻ (E = S, Se, Te) and c) the peri-substitution of phosphorus and tellurium atoms on an acenaphthene backbone. The use of sterically demanding substituents led to the isolation of the first series of structurally characterised organophosphorus(III)-tellurium heterocycles of the type (RP)[sub]nTe[sub]m including three- to six-membered ring systems. The mild oxidation of [{EP(NtBu)(μ-NtBu)}₂]²⁻ (E = S, Se, Te) with iodine yielded macrocyclic (S, Se) or oligomeric systems (Te). Furthermore, a collection of novel P₂N₂-supported phosphorus-chalcogen heterocycles incorporating main group elements was synthesised employing [{EP(NtBu)(μ-NtBu)}₂]²⁻ (E = S, Se, Te) in metathetical reactions with main group element halides. Extension of this approach to transition metal halides generated some unusual metallocycles, as well as macrocycles and ladders incorporating coinage metals. The first peri-substituted phosphorus-tellurium species were studied regarding their interatomic and intermolecular forces. Systems of the general formula RTe–Acenap–P(iPr)₂ were shown to exhibit extensive through-space spin-spin coupling. In addition, the influence of oxidation and complexation on these interactions was investigated and the formation of peri-substituted phosphorus-tellurium cations exhibiting P–Te bonds was observed.

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29

De, Brabandere Heidi. "Organic Phosphorus Compounds in Aquatic Sediments : Towards Molecular Identification with Mass Spectrometry." Doctoral thesis, Uppsala universitet, Institutionen för fysikalisk och analytisk kemi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9319.

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Phosphorus (P) regulates trophic status in most aquatic systems. However, only bioavailable P contributes to primary production. In most lakes and shallow seas, mineralisation of sediment P into its bioavailable form and its release to the water column is important for maintaining primary production. Sediment organic P forms a substantial proportion of this P to be mineralised and can originate from different sources on land (farmland, forests, etc.) or from primary production in the lake. These organic P forms can thus be expected to have differing composition, degradability and recyclable P content. Knowledge of the chemical structure of sediment organic P compounds is scarce, mainly due to lack of appropriate analytical techniques. The commonly used 31P-nuclear magnetic resonance (31P-NMR) technique, only identifies P binding groups, so a mass spectrometric (MS) analysis method was developed that allows individual sediment organic P compounds to be identified. EDTA as pre-extractant resulted in the highest P yield in subsequent NaOH extraction. Extracted organic P compound groups were identified using 31P-NMR. For identification of specific P compounds with MS, a sample preparation method prior to electrospray tandem mass spectrometry (ESI-MS/MS) analysis was developed. Liquid chromatography (LC) with porous graphitic carbon prior to ESI-MS/MS enhanced sensitivity and selectivity, enabling several of the ions detected to be identified as nucleotides. 31P-NMR analysis showed P monoesters to be the most stabile P compounds throughout a lake sediment profile. The developed LC-ESI-MS/MS analysis method revealed that some monoester-P (nucleotides) were labile, while other P compounds increased in concentration with Baltic Sea sediment depth and were therefore considered stabile. Differences in patterns of P compounds detected were also shown depending on catchment characteristics in relation to Baltic Sea sediment age. For cost-effective management of eutrophication, knowledge of the sources of degradable organic P forms, contributing to internal loading, is needed. This thesis showed the developed LC-ESI-MS/MS analysis method to be a powerful analytical tool for this purpose.

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Bullett, Kelly Jane. "Flame retarding acrylic and styrenic polymers by modification with phosphorus-containing compounds." Thesis, University of Salford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395658.

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31

Jones, Nicole Jean. "NITRIFYING BACTERIAL ABUNDANCE IN RELATION TO NITROGEN AND PHOSPHORUS COMPOUNDS IN WETLANDS." OpenSIUC, 2012. https://opensiuc.lib.siu.edu/theses/829.

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Floodplain lakes are wetlands which receive flood waters from nearby rivers or other sources. Water samples were taken from floodplain lakes near the Illinois River, the Mississippi River, and the Cache River in Southern Illinois. Fluorescence in situ hybridization (FISH), spectrophotometry, and gene probes were used to investigate the effect of nutrient and chemical concentrations on the abundance of nitrifying bacteria; specifically ammonia-oxidizing Nitrosococcus and Nitrosomonadales and nitrite-oxidizing Nitrospira and Nitrobacter. Nitrosococcus was the dominant ammonia-oxidizing bacteria at each river system. Nitrospira and Nitrobacter had similar average abundances. Nitrosococcus abundances showed a significant positive correlation with nitrate (NO3-) (R2= 0.247, P=0.05, 95% confidence R2≥0.199) and a positive trend with nitrite (NO2-) (R2= 0.194, P=0.10, 90% confidence R2≥0.125). Nitrosomonadales abundance positively correlated with temperature (R2= 0.530, P=0.05, 95% confidence R2≥0.510). Nitrospira abundances positively correlated with ammonium (NH4+) (R2= 0.265, P=0.05, 95% confidence R2≥0.199), NO2- (R2= 0.372, P=0.05, 95% confidence R2≥0.199), and NO3- (R2= 0.482, P=0.05, 95% confidence R2≥0.199). None of the target bacterial abundances significantly correlated with pH or dissolved inorganic phosphate.

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Tieman, Tamara L. "A Helium Discharge Detector for the Determination of Organosulfur and Phosphorus Compounds." W&M ScholarWorks, 1992. https://scholarworks.wm.edu/etd/1539625734.

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33

Wong, Kwok-ming, and 黃國明. "Ruthenium-nitrogen and ruthenium-phosphorus multiple bonds supported by phthalocyanines: syntheses, spectroscopicproperties, and reactivities." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45545893.

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Lee, Wing Sze. "Preparation of doubly p-chiral phosphine oxides for asymmetric catalysis /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202003%20LEE.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.
Includes bibliographical references (leaves 135-142). Also available in electronic version. Access restricted to campus users.

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35

Austen, Maggie A. Bader R. F. W. "A new procedure for determining bond orders in polar molecules, with applications to phosphorus and nitrogen containing systems /." *McMaster only, 2003.

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36

Masuda, Jason Douglas, and University of Lethbridge Faculty of Arts and Science. "The monophosphaamidine functional group." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2002, 2002. http://hdl.handle.net/10133/191.

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The synthesis and characterization of two new bulky N,P-monophosphaamidines (also known as C-aminophosphaalkenes) are described. These phosphorus analogues to amidines are shown to exhibit isomerism and tautomerism in solution that is characteristic tothe amidine functional group. In addition, the nature of the P=C-N system is examined using DFT techniques. Metal complexes of the title compounds with Group 6 metal carbonyls (L-M(CO)5, M=Cr,Mo,W) are also described. A new primary phosphane is reported that contains the sterically bulky, 2,6-diisoropylphenyl (Dip) group, along with mono and disilylated derivatives. Also included is the synthesis and characterization of a new bulky N,N',P-monophosphaguanidine.
xxxii, 280 leaves : ill. ; 28 cm.

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37

Roden, M. D. "Synthesis and characterisation of some novel low-coordinate phosphorus compounds containing bulky electron-withdrawing substituents." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4692/.

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The synthesis of several new phosphorus derivatives including new monophosphanes of the type RPX(_2) (X = F, CI and H), containing either the Fluoromes [2,4,6-(CF(_3))(_3)C(_6)H(_2)] or Fluoroxyl [2,6-(CF(_3))(_2)C(_6)H(_3)] group has been carried out successfully. The synthesis of a number of Cis-Platin analogous has been facilitated by the reaction of these new monophosphanes with a platinum dimer [(PCl(_2)(Pet(_3))(_2)](_2). These compounds are of the type PtCl(_2)(Pet(_3))RPX(_2) (X = CI, H and F, R = 2,6- bis(trifluoromethyl)phenyl). These compounds have shown an interesting correlation between bond length and (^1)J(_p-pt) NMR coupling. Disubstituted phosphanes (RPX(_2), X = CI, H) have also been synthesised and subsequent reaction has facilitated the formation, characterisation and structure solution of a new phosphorus (I) species (RP(_2)(^(-)))(Ph(_3)PCH(_3))(^1) (R - Fluoromes).Attempts have been made to synthesise the first phosphaalkyne containing a bulky electron withdrawing ligand. This involved the reaction of RP=CCl(_2) (R = 2,6- bis(trifluoromethyl)phenyl) with a number of Pt(0) and Pd(0) species. (^31)P NMR studies have been used extensively throughout the project to help characterise and identify the products. The single crystal, solid state structures of many of the new species were elucidated by X-ray diffraction using a Siemens Smart CCD.

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38

Valls, Cantenys Carme. "Development of analytical methodologies for the determination of emerging contaminants and phosphorus compounds." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/284742.

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The presence of anthropogenic chemical substances in water resources can affect the ecological balance of aquatic systems, as well as human health, and therefore it is necessary to control their presence in water bodies. The objective of this thesis is the development of analytical methodologies for the determination of phosphorus species and organic micropollutants in water samples. Firstly, two speciation methods for the determination of simple and condensate phosphorus oxoanions have been developed, using HPLC separation coupled to ICP-AES in one methodology and to ICP-MS in the other. Two analytical methodologies have been developed for the determination of endocrine disrupting compounds using PDMS rod extraction. The determination was carried out by GC-MS for flame retardants and by HPLC-DAD for phenolic compounds. Finally, a multiresidue method based on SPE followed by LC-MS/MS have been developed for the determination of 35 analytes, including pharmaceuticals, corrosion inhibitors, and pesticides, in water samples
La contaminació de l’aigua per compostos d’origen antropogènic pot afectar tant al medi ambient com a la salut humana i per tant és necessari controlar-ne la presència. L’objectiu de la tesi és desenvolupar metodologies analítiques per a determinació de espècies de fòsfor i microcontaminants orgànics en mostres d’aigua. En primer lloc, s’han desenvolupat dos mètodes d’especiació per a la determinació de oxoanions de fòsfor simples i condensats, mitjançant separació per HPLC acoblada a ICP-AES en un mètode, i a ICP-MS en l’altre. També s’han desenvolupat dos mètodes utilitzant extracció amb cordó de PDMS per a la determinació de compostos que actuen com a disruptors endocrins. La determinació es va portar a terme per GC-MS per als retardants de flama bromats i per HPLC-DAD per als compostos fenòlics. Finalment es va desenvolupar un mètode multiresidu basat en SPE seguit de LC-MS/MS per a la determinació de 35 analits, incloent compostos farmacèutics, inhibidors de la corrosió i plaguicides

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39

Gray, Andrew. "Investigation into the fate and transport in groundwater of agriculturally derived phosphorus compounds." Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/55029/.

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Investigation into the fate and transport in groundwater of agriculturally derived phosphorus compounds Phosphates are ubiquitous in the environment, where they are essential for life however at excessive levels they can cause significant environmental damage. This project investigates the spatial and temporal occurrence of phosphorus in groundwater, and phosphorus transport through the vadose zone. Concentrating on agriculturally-derived phosphates, the research elucidates the geochemical relationships between phosphorus species and geology. The project has two study locations. A section of the Lower Usk Valley in Monmouthshire was the principal site the Eden Valley in Cumbria was used as a comparison case study. With highly heterogeneous distributions, phosphorus often showed significant concentrations in both soil and groundwater. In groundwater Soluble Reactive Phosphorus (SRP) ranged from 1.07 mg I"1 to undetectable. Maximum soil leachable SRP was measured at 55 mg kg"1 and soil Total Phosphorus (TP) 113 mg kg"1 while in an adjacent borehole groundwater SRP was undetectable. Phosphorus was found at intermediate concentrations beneath potential hotspots created by large manure piles effluent 85 mg I"1. Analysis by X-ray diffraction and analytical scanning electron microscopy did not identify soil phosphate minerals at these and other sites this suggests that precipitation reactions are not a dominant source or sink of agricultural phosphorus in local soils. The results of the geochemical investigations indicates that iron and manganese oxides are providing sorption sites for phosphates, influencing their mobility and observed concentration in groundwater. Data obtained from in-situ borehole loggers were used to characterise the aquifer zone of the study area and understand the groundwater response to external drivers such as fertilizer application and rainfall. Groundwater and species transport modelling of the Usk area indicates that local parameter heterogeneity is critically important. The groundwater modelling, supported by a statistical analysis of the data, has increased and refined our conceptual understanding of the fate and transport of phosphorus in groundwater.

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40

Fleming, Conor Gareth Edward. "Geminally bis(supermesityl) substituted phosphorus compounds and a study of 5,6-substituted-acenaphthenes." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/3553.

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This thesis describes the effect of placing a phosphorus atom in a sterically strained environment with particular emphasis on the geminal disubstitution of two 2,4,6-tri-tert-butylphenyl (Mes*) groups on a single phosphorus centre and intramolecular sub-van der Waals interactions between peri-substituted atoms on naphthalene and acenaphthene. Chapter 2 outlines the reactive chemistry of a sterically encumbered phosphinic chloride (Mes*)₂P(=O)Cl, which was shown to have extremely low reactivity at the phosphorus centre. It has however, been demonstrated that synthetically significant transformations are possible. The phosphine oxide (Mes*)₂P(=O)H and a secondary phosphine Mes*(2,4-tBu₂C₆H₃)PH were obtained from the reduction of (Mes*)₂P(=O)Cl with hydridic reagents under forcing conditions. The corresponding phosphinite was acquired from the deprotonation of (Mes*)₂P(=O)H, which furnished very crowded tertiary phosphine oxides (Mes*)₂P(=O)R (R = Me and Et) on reactions with electrophiles. We have been unable to chlorinate or deprotonate Mes*(2,4-tBu₂C₆H₃)PH, however the reaction with elemental sulfur afforded the affiliated phosphine sulfide Mes*(2,4-[supercript(t)]Bu₂C₆H₃)P(=S)H, albeit under forcing conditions. Our computations (B3LYP and M06-2X level) show that strain energies of geminally substituted compounds are extremely high (180 to 250 kJ mol⁻¹), the majority of the strain is stored as boat distortions to the phenyl rings in Mes* substituents. Chapter 3 describes the strain inherent with non-bonding atomic distances shorter than the sum of their van der Waals radii, specifically heteroatom substitution of the peri-positions of naphthalene and acenaphthene. It also documents the importance of amine protecting groups in chlorophosphine chemistry. The preparation of Ace[P(Ph)N(ⁱPr)₂]Br (Ace = acenaphthene-5,6-diyl) and Ace[P(Ph)N(ⁱPr)₂]₂, plus the elucidation of the molecular structures of Mes*P[N(CH₃)₂]₂, Ace[P(Mes)N(ⁱPr)₂]Br (Mes = 2,4,6-tri-methylphenyl) and Ace[P([supercript(t)]Bu)N(Et)₂]Br sufficiently demonstrate the ring distorting characteristics of structurally encumbered molecules. The reaction of Ace[P(Ph)N(ⁱPr)₂]Br and Ace[P(Ph)N(ⁱPr)₂]₂ with a methylating agent was also investigated.

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41

Cao, Yu. "The synthesis of organo-phosphorus transition-state analogue inhibitors of dihydroorotase." Master's thesis, Canberra, ACT : The Australian National University, 1994. http://hdl.handle.net/1885/141358.

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42

Lang, Stephen J. "Infrared and solid state NMR studies of the adsorption of phosphorus compounds on oxides." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/9575.

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Infrared and Solid State NMR spectroscopies have been used to study the reactions of $\rm PMe\sb{n}Cl\sb{3-n}$ (n = 0 to 2) with silica, the reactions of P(OMe)$\sb3$ and related compounds with alumina, as well as the adsorption of PMe$\sb3$ on a variety of oxides. PMe$\sb3$ interacts with silica activated at moderate temperatures via hydrogen bonding or physisorption only. PCl$\sb3$ interacts with silica at room temperature via a weak hydrogen bonding interaction. Previous assignments in the literature of two kinds of hydrogen bonded complex are shown to be in error. OPCl$\sb3$, often present as an impurity in PCl$\sb3$, is shown to be responsible for the infrared peaks that had previously been incorrectly assigned to a second type of adsorbed PCl$\sb3$. Prolonged room temperature reaction led to the formation of small amounts of $\equiv$Si-O-PCl$\sb2$, ($\equiv$SiO)$\sb2$P(H)=O, $\equiv$SiOP(H)OH, and another unidentified product. vskip18pt PMe$\sb2$Cl was much more reactive. It reacts to form $\equiv$Si-O-P(O)Me$\sb2$, removing most of the surface silanol groups in the process. The identity of this species could be verified by both IR and NMR. IR spectra of a thin film of $\sp $O exchanged silica showed that this compound definitely does extract oxygen from the silica surface. PMeCl$\sb2$ shows intermediate reactivity towards silica. Most of the surface silanol groups are consumed after four or five hours reaction time. The dominant phosphorus containing surface species is $\equiv$Si-O-P(O)(H)Me. Dimethyl methylphosphonate (DMMP) reacts with $\rm Al\sb2O\sb3$ by losing its methoxy groups in a sequential manner. For room temperature interaction molecular DMMP, either hydrogen bonded to the surface or coordinated to Lewis acidic aluminium atoms, is the predominant species. After reaction at 100$\sp\circ$C most of the DMMP molecules have lost one methoxy group. After 300$\sp\circ$C reaction all of the DMMP has lost both of its methoxy groups. Dimethyl phosphite (DMP) reacts in a similar manner to DMMP, although some P-Me groups form during the reaction, indicating that $\rm Al\sb2O\sb3$ can cleave the P-H bond of dialkyl phosphites. Trimethyl phosphite reacts with $\rm Al\sb2O\sb3$ to give all of the products observed in the reactions of DMMP and DMP with $\rm Al\sb2O\sb3$. Many of the magic-angle-spinning NMR spectra presented in this thesis were acquired with pulse sequences that result in the Total Suppression of Sidebands (TOSS). For completeness, a similar mathematical treatment of pulse sequences that produce Phase Adjusted Spinning Sidebands (PASS) is also presented. Two interesting new pulse sequences that produce Hahn echoes in rotating samples are demonstrated. (Abstract shortened by UMI.)

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43

White, Colin L. "Mechanism & stereochemistry of some reactions of IV- & V- co-ordinated phosphorus compounds." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/33991.

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A series of cyclic phosphoranes and spirophosphoranes have been prepared and reacted with diethyl phosphorochlor- idite, the phosphorane acting as a nucleophile, and the subsequent products reacted further with methyl iodide and chloral. Reactions have also been carried out in which a nucleophilic attack on the phosphorane occurs, the nucleophile employed being the anion of thio-phenol. It was hoped these reactions might provide a new pathway to the type of phosphorus compound which have been involved for a number of years in the control of pestsoniiosects and that an insight into the stereoelectronic requirements of reactions at phosphorus might be obtained. The mechanism of the Michaelis-Arbusov rearrangement is generally accepted as having a two stage pathway, the second stage usually considered as being an SN2 attack of a nucleophile on the a-carbon of an alkyl group. Arbusov and related reactions with unsymmetrical phosphites containing different alkyl groups have been carried out. The effect of varying the electrophile, nucleophile, temperature and solvent of the reactions has been studied. As a result of the above, the second stage of the generalised Arbusov reaction is found to have SNl character. The stereochemistry of nucleophilic substitution at phosphoryl centres has been studied extensively by a number of groups. However, it has not hitherto been possible to investigate the stereochemistry of hydrolyses since these lead to achiral acids. A general method, involving isotopic labelling, has been developed that allows the stereochemistry of such hydrolyses to be established. The stereochemistry of the alkaline hydrolyses of Sp-methyl methylphenylphosphinate and methylphenylthiophosphinate have been established using the method referred to above.

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44

Bain, David Leslie Kenneth. "Reactions of phosphide anions single electron transfer and routes to optically active phosphorus compounds." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356886.

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45

Mampa, Richard Mokome. "X-ray and NMR spectropscopic studies of selected heterocyclic compounds of phosphorus and nitrogen /." Pretoria : [s.n.], 2000. http://upetd.up.ac.za/thesis/available/etd-02092006-155713/.

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46

Du, Junyi. "X-ray crystallographic studies of sulfur/selenium heteroatom compounds." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8984.

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The major aim of research reported on this thesis uses X-ray crystallography to investigate the structural features of a series of pentafluorosulfuranyl (SF₅) containing aromatic compounds, chalcogen amides, 2,4-diaryl-1,3-selenazoles and 2,4-diaryl-1,3-chalcogen azoles bearing SF₅ group and organo phosphorus-chalcogen macrocycles incorporationg double OP(S)SC[sub]n or OP(Se)SeC[sub]n scaffolds. The basic theory of crystallography is introduced in Chapter 1, followed by a general discussion on pentafluorosulfuranyl (SF₅) containing heteroatom compounds and sulfur/selenium heterocycles in Chapter 2. Ten pentafluorosulfuranyl (SF₅)-containing aromatic compounds have been studied crystallographically in Chapter 3. All S-F bond lengths in these compounds are very similar [1.571(3) to 1.618(3) Å and 178.5(3) to 180.0° for the C-S-F(ax) bond] and the angles of two adjacent F(eq) is approximate to 90°. The intramolecular C[sub](aryl)-H···F(eq) and intermolecular C[sub](aryl)-H···O/N/F/Cl interactions, and π-stacking interactions are observed in the packing frameworks. X-ray crystal structure analysis reveals that in the structures of 2,4-diaryl-1,3-selenazoles in Chapter 4, the five-membered N-C-Se-C-C rings have either planar or near-planar conformations, and exhibit a series of the intramolecular and intermolecular C-H∙∙∙O/N/Se/Br/Cl) interactions and π-stacking interactions. The crystal structures of 2,4-diaryl-1,3-chalcogen azoles with both a pentafluorosulfuranyl (SF₅) group and a five-membered N-C-Se-C-C ring have been investigated in Chapter 5. A diverse picture of molecular configuration and intramolecular/intermolecular C-H∙∙∙N/Se/S and π-stacking interactions information are disclosed in selenamide, thiamides, 1,3-selenazoles and 1,3-thiazoles. Nine organo phosphorus-chalcogen macrocycles with nine- to fifteen-membered ring incorporating double OP(S)SC[sub]n or OP(Se)SeC[sub]n scaffolds have been discussed crystallographically in Chapter 6. The similar intramolecular and intermolecular C-H∙∙∙O, C-H∙∙∙S or C-H∙∙∙Se interactions are observed to lead to the similar packing networks.

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47

Armstrong, Kenneth Mark. "Catalytic synthesis of organophosphate plastics additives from white phosphorus." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2587.

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Triaryl phosphates were synthesized from white phosphorus and phenols in aerobic conditions and in the presence of iron catalysts and iodine. Full conversion to phosphates was achieved without the use of chlorine or chlorinated solvents, and the reactions do not produce acid waste. Triphenyl phosphate, tritolyl phosphate and tris(2,4-di-tert-butyl)phenyl phosphate were synthesized by this method with 100% conversion from P₄. Various iron(III) diketonates were used to catalyse the conversion. Mechanistic studies showed the reaction to proceed via the formation of phosphorus triiodide (PI₃), then diphenyl phosphoroiodidate (O=PI(OPh)₂) before the final formation of triphenyl phosphate (O=P(OPh)₃). The nucleophilic substitution of O=PI(OPh)₂ with phenol to form O=P(OPh)₃ was found to be the rate determining step. It was found that by modifying the reaction conditions the same catalytic systems could be used to synthesize triphenyl phosphite directly from P₄. Triphenyl phosphite was synthesized in selectivities of up to 60 %. The mechanism of these transformations was also elucidated. Independent syntheses of the intermediate in the reaction mechanism, O=P(OPh)₂I and its hydrolysis products diphenyl phosphate (O=P(OPh)₂OH) and tetraphenyl pyrophosphate ((O)P(OPh)₂-O-P(O)(OPh)₂) were developed from PI₃. The 2,4-di-tert-butyl phenol analogues of these compounds were also prepared. Bis-(2,4-di-tert-butylphenyl) phosphoroiodidate was then reacted with various alcohols to produce a series of mixed triorgano phosphates.

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48

Schmid, Thibault E. "Synergism between N-heterocyclic carbene and phosphorus-based ligands in ruthenium and palladium catalytic systems." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3452.

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N-heterocyclic carbenes (NHCs) have become a very popular class of ligands, which has found uses in numerous catalytic applications. The use of such compounds in combination with phosphorus-based ligands within metal complexes has enabled the design of very active yet robust catalytic systems. The following chapters will describe the design of novel well-defined palladium- and ruthenium-based pre-catalysts featuring a NHC and a phosphorus-based ligand, referred at as mixed ligand systems. Such species were employed in catalysis where their properties appeared highly beneficial, uses at low catalysts loading and under harsh conditions were then envisioned. The preparation of a series of well-defined palladium mixed NHC/phosphine species is presented in chapter 2. Their catalytic activity in the aqueous Suzuki-Miyaura reaction of aryl chlorides and boronic acids, using low catalyst loadings, is described. The observation of catalytic activity of the latter systems in the hydration of nitriles prompted us to further investigate this reactivity. This reaction appeared to be operative in the absence of palladium species and could be performed under base-catalysed conditions, which was studied in detail and depicted in chapter 3. The combination of a NHC and a phosphite ligand in ruthenium olefin metathesis pre-catalysts has been underexplored. Preliminary results showed that such species could be readily prepared and presented an unusual geometry and a high catalytic activity. Variations in phosphite-containing ruthenium olefin metathesis pre-catalysts are presented. Chapter 4 describes the investigation of various Schrock carbene moieties in such architectures, as well as their implications in structure and catalysis. Chapter 5 depicts attempts to design olefin metathesis Z-selective pre-catalysts by inserting a chelating NHC moiety within phosphite-containing ruthenium species. This dissertation concludes on the potential of such mixed species in catalysis, and armed with the new knowledge provided by this work, proposes potential developments of such chemistry in the design of always more robust and active catalytic systems.

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Hill, Stephen Bernard. "Utilisation of phosphorus containing compounds to modify the properties of poly(methyl methacrylate) based polymers." Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369465.

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50

Frew, Jamie J. R. "Novel bulky fluorinated ligands for homogeneous catalysis." Thesis, University of St Andrews, 2008. http://hdl.handle.net/10023/852.

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A series of novel monodentate and bidentate phosphine ligands substituted with bulky tert-butyl and fluorinated aryl groups have been synthesised. Borane protection has proved to be an excellent method for easy synthesis and purification of bidentate ligands in some cases. However, several of the bulky fluorinated ligands do not form stable borane complexes leading to complications in the synthesis and purification of these compounds. By reaction with transition metal platinum and palladium precursors, it was possible to form dichloride complexes from the synthesised ligands, which were characterised by X-ray crystallography. The complexes were found to be effective catalysts for the hydroxycarbonylation of vinyl arenes (yields of up to 95 % with 3 mol% catalyst). An unsymmetrical bidentate complex (3.18) in combination with paratoluenesulfonic acid and LiCl promoters has given exceptional (for a diphosphine ligand) regioselectivity for the branched acid (98.7 % branched) in the hydroxycarbonylation of styrene. The role of the promoters has been found to be crucial in deciding the activity and selectivity in this reaction.

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Dissertations / Theses on the topic 'Phosphorus compounds'

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