No description available.

<p>In this thesis oxidative coupling of H-phosphonate and H phosphonothioate diesters with different alcohols and amines are presented. Since the reactions with alcohols previously have been particularly unfavourable due to competing side reactions, a modified protocol leading to high coupling yields of structurally diverse hydroxylic components was developed. The phosphorylation reaction was studied using ³¹P NMR spectroscopy and for the first time the previously only postulated reactive intermediate involved in these reactions was observed. </p><p>The use of iodine in combination with a bulky chlorosilane in pyridine was found to have a profound effect on both the suppression of side reactions and the rate of the oxidative couplings, and led to a clean formation of phosphorylated products in high yields. This synthetic protocol was then extended to include coupling reactions with bis-functional reagents containing hexamethylene linkers to provide handles for derivatisations of oligonucleotides.</p><p>A synthetic protocol consisting of the stereospecific oxidative coupling of amines with H-phosphonate diesters to produce phosphoroamidates was designed in such a way that it permitted control of the stereochemical outcome of the reactions.</p><p>Based on a silylation-mediated reaction utilising phenyl H phosphonothioate monoester as a thiophosphonyl transferring agent, a method was developed and used for the preparation of H-phosphonothioate building blocks for the synthesis of DNA analogues.</p>

Phosphonate antiscalants are commonly used in nanofiltration and reverse osmosis water treatment to prevent membrane fouling by mineral scale. In many circumstances it is desirable to remove these phosphonate compounds before concentrate disposal or further treatment. This research investigated the removal of phosphonate compounds from simulated membrane concentrate solutions using ferric hydroxide adsorbents. Two phosphonate antiscalants were investigated, Permatreat 191® (PT191) and nitrilotrimethylphosphonic acid (NTMP). Batch adsorption isotherms and column breakthrough and regeneration experiments were performed on two commercial adsorbents and a ferric hydroxide loaded polyacrylonitrile fiber adsorbent prepared in our laboratory. The best performing adsorbent was Granular Ferric Hydroxide® (GFH) obtained from GEH Wasserchemie. Adsorption isotherms measured after 24-hour equilibration periods showed initial concentration effects, whereby the isotherms were dependent on the initial adsorbate concentration in solution. Significant differences in adsorption behavior were observed between the PT191 and the NTMP adsorbates. Differences in adsorption behavior between NTMP and PT191 are all consistent with the PT191 containing fewer phosphonate functional groups per molecule than NTMP. Desorption rates were bimodal, with 40-50% of the adsorbed phosphonate being released on a time scale of 10-24 hours, while the remaining fraction was released approximately one order of magnitude more slowly. The slow desorbing fraction primarily resulted from equilibrium effects resulting from significant phosphonate adsorption, even in 1.0 mol/L NaOH solutions. Complete regeneration could not be achieved, even after eluting the adsorbent columns with more than 300 bed volumes of 1.0 mol/L NaOH. However, the incomplete regeneration had only a minor effect on phosphonate uptake in subsequent column breakthrough experiments.

Measurement and mapping of the pressure distribution across the surface of a suitably scaled model is an integral step in the design of any aircraft or automobile. For this purpose, the traditional workhorses of the aeronautic and automotive industries have been pressure taps--small orifices that contain electronic pressure transducers. Unfortunately, in addition to the limited spatial resolution achievable with such devices, their technical complexity and cost constitute serious disadvantages. For more than 35 years, researchers have pursued a fundamentally different alternative: indirect measurement of pressure via oxygen-induced quenching of the luminescence emitted by certain chemical species. Porphyrin complexes of dipositive palladium and especially platinum have emerged as one of the principal classes of oxygen-sensitive luminophores; ruthenium(II) polypyridyl complexes comprise another. Various other metals also form luminescent coordination complexes that are susceptible to quenching by O2, however, and these too have contributed to the diversity of luminophores that are now available for incorporation into pressure-sensitive paints and related films and coatings. After treating the photophysics of luminescence quenching by molecular oxygen and quantitative descriptions of this phenomenon in the ideal case and in heterogeneous media, the thesis presents a comprehensive survey of the chemical literature on oxygen-sensitive luminophores. Efforts to prepare and characterize a novel porphyrin-pillared mixed zirconium phosphonate are then detailed. Following complexation of Pt(II) ions by the porphyrin moieties, this material is expected to display oxygen-sensitive luminescence and should ameliorate such difficulties as luminophore aggregation and matrix photodegradation that are associated with many existing pressure-responsive coatings. Its preparation necessitated preliminary formation of a porphyrin functionalized with two phenylphosphonic acid groups, which was obtained by synthesizing dipyrromethane and diethyl 4-formylphenylphosphonate and condensing these two precursors. The mixed phosphonate, a layered material assembled from ZrOCl2 · 8H2O, methylphosphonic acid, and the aforementioned porphyrin, was then prepared in refluxing HF. Solid-state 31P NMR spectra and powder X-ray diffraction patterns were acquired for the final product, its estimated interlayer spacing of 22.8 Å figuring prominently in analysis and discussion of the X-ray data.

Title: Cross-bridged cyclams as manganese(II) chelators Autor: Bc. Luděk Míka Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: doc. RNDr. Jan Kotek, Ph.D. Supervisor's e-mail address: modrej@natur.cuni.cz Abstract: The aim of this project was to synthesize a new kind of Mn(II) complexes with ligands derived from cross-bridged cyclam. These complexes may be potentially used as contrast agents in magnetic resonance imaging. Six macrobicyclic ligands with various pendant arm were synthesized, three complexes were sucesfully prepared. Electrochemical properties of prepared manganese(II) complexes with synthesized ligands were studied using cyclic voltammetry. Relaxivity of prepared complexes was determined by 1 H NMR spectroscopy. Keywords: cross-bridged cyclam, phosphonate, phosphinate, pendant arms, manganese

Les polymères fluorés sont des macromolécules intéressantes qui, en raison de leurs propriétés uniques, sont souvent utilisées dans des applications spéciales dans les industries du bâtiment, de l'aérospatiale, du génie chimique, du traitement des textiles, optiques et de la microélectronique. Cette thèse se concentre sur le développement de polymères fluorés fonctionnels à base de phosphore et de silane par la co/terpolymérisation radicalaire conventionnelle de monomères fonctionnels avec le fluorure de vinylidène (VDF). Ces monomères fonctionnels ont été préparés à partir de la modification de l'acide 2- (trifluorométhyl) acrylique (MAF) pour préparer des MAF-ester avec le groupement fonctionnel souhaité. Tout d'abord, une étude fondamentale concernant la cinétique de polymérisation du VDF avec MAF-TBE a montré que ces paires de monomères ont une tendance à se propager de manière croisée, ce qui donne des copolymères alternés. On a ensuite préparé du MAF avec une fonction phosphonate (MAF-DMP) et sa copolymérisation avec du VDF a permis d'obtenir du PVDF à fonctionnalité phosphonate qui, après l'hydrolyse consécutive du groupe phosphonate en acide phosphonique, avait des propriétés anticorrosion sur l'acier. De façon similaire, un monomère de MAF porteur une fonction carbonate cyclique (MAF-cyCB) a également été copolymérisé avec du VDF. Les groupes carbonate cycliques dans le copolymère de PVDF obtenu ont ensuite été ouverts par 1'aminopropyltriéthoxysilane pour introduire un groupe silane, qui, par son hydrolyse, a permis au copolymère d'adhérer fortement sur les substrats. Enfin, un terpolymère à base de PVDF fonctionnel porteur à la fois un groupe phosphonate et un groupe triéthoxysilane a été préparé. Le groupe silane a ensuite été hydrolyse et réticulé pour obtenir un réseau 3D de polymères. Enfin, l'hydrolyse du groupe phosphonate en acide phosphonique a conduit à une matière pouvant être utilisée dans l'extraction des ions Eu (III) de l'eau. / Fluorinated polymers are intresting macromolecules which due to their unique properties are often used in special applications in building industries, aerospace, chemical engineering, optics, textile treatment and microelectronics. This thesis focusses on the development of phosphorous and silane functional fluorinated polymers through the conventional radical co/terpolymerization of functional monomers with vinylidene difluoride (VDF). These functional monomers were prepared from the modification of 2-(Trifluoromethyl)acrylic acid (MAF) to prepare MAF-esters with the desired functional group. First a fundamental study regarding the kinetics of polymerization of VDF with MAF-TBE revealed that these monomer pair tends to cross propagate resulting in an alternating copolymer. Phosphonate functional MAF (MAF-DMP) was then prepared and its copolymerization with VDF led to phophonate functional PVDF, that after the consequent hydrolysis of the phosphonate group into phosphonic acid showed anticorrosion properties to steel. Following the same concept, a cyclic carbonate functional MAF monomer (MAF-cyCB) was also copolymerized with VDF. The cyclic carbonate groups in the obtained PVDF copolymer was then opened by aminopropyltriethoxysilane to introduce a silane group, that by its hydrolysis allowed the copolymer to adhere strongly onto substrates. Finally, a terpolymer based on PVDF functional with both a phosphonate and a triethoxysilane group is prepared. The silane group was then hydrolyzed and crosslinked to obtain a 3D network of polymers. Finally, the hydrolysis of the phosphonate group into phosphonic acid led to material that can be employed in Eu(III) ion extraction from water.

<p>In this thesis, the chemistry of compounds containing P-Se bonds has been studied. As a new addition to this class of compounds, H-phosphonoselenoate monoesters, have been introduced and two synthetic pathways for their preparation have been developed.</p><p>The reactivity of H-phosphonoselenoate monoesters towards a variety of condensing agents has been studied. From these, efficient conditions for the synthesis of H-phosphonoselenoate diesters have been developed. The produced diesters have subsequently been used in oxidative transformations, which gave access to the corresponding P(V) compounds, <i>e.g</i>. dinucleoside phosphoroselenoates or dinucleoside phosphoroselenothioates.</p><p>Furthermore, a new selenizing agent, triphenyl phosphoroselenoate, has been developed for selenization of P(III) compounds. This reagent has high solubility in organic solvents and was found to convert phosphite triesters and H-phosphonate diesters efficiently into the corresponding phosphoroselenoate derivatives.</p><p>The selenization of P(III) compounds with triphenyl phosphoroselenoate proceeds through a selenium transfer reaction. A computational study was performed to gain insight into a mechanism for this reaction. The results indicate that the transfer of selenium or sulfur from P(V) to P(III) compounds proceeds most likely <i>via</i> an X-philic attack of the P(III) nucleophile on the chalcogen of the P(V) species. For the transfer of oxygen, the reaction may also proceed <i>via</i> an edge attack on the P=O bond.</p>

No description available.

In this thesis oxidative coupling of H-phosphonate and H phosphonothioate diesters with different alcohols and amines are presented. Since the reactions with alcohols previously have been particularly unfavourable due to competing side reactions, a modified protocol leading to high coupling yields of structurally diverse hydroxylic components was developed. The phosphorylation reaction was studied using 31P NMR spectroscopy and for the first time the previously only postulated reactive intermediate involved in these reactions was observed. The use of iodine in combination with a bulky chlorosilane in pyridine was found to have a profound effect on both the suppression of side reactions and the rate of the oxidative couplings, and led to a clean formation of phosphorylated products in high yields. This synthetic protocol was then extended to include coupling reactions with bis-functional reagents containing hexamethylene linkers to provide handles for derivatisations of oligonucleotides. A synthetic protocol consisting of the stereospecific oxidative coupling of amines with H-phosphonate diesters to produce phosphoroamidates was designed in such a way that it permitted control of the stereochemical outcome of the reactions. Based on a silylation-mediated reaction utilising phenyl H phosphonothioate monoester as a thiophosphonyl transferring agent, a method was developed and used for the preparation of H-phosphonothioate building blocks for the synthesis of DNA analogues.

In this thesis, the chemistry of compounds containing P-Se bonds has been studied. As a new addition to this class of compounds, H-phosphonoselenoate monoesters, have been introduced and two synthetic pathways for their preparation have been developed. The reactivity of H-phosphonoselenoate monoesters towards a variety of condensing agents has been studied. From these, efficient conditions for the synthesis of H-phosphonoselenoate diesters have been developed. The produced diesters have subsequently been used in oxidative transformations, which gave access to the corresponding P(V) compounds, e.g. dinucleoside phosphoroselenoates or dinucleoside phosphoroselenothioates. Furthermore, a new selenizing agent, triphenyl phosphoroselenoate, has been developed for selenization of P(III) compounds. This reagent has high solubility in organic solvents and was found to convert phosphite triesters and H-phosphonate diesters efficiently into the corresponding phosphoroselenoate derivatives. The selenization of P(III) compounds with triphenyl phosphoroselenoate proceeds through a selenium transfer reaction. A computational study was performed to gain insight into a mechanism for this reaction. The results indicate that the transfer of selenium or sulfur from P(V) to P(III) compounds proceeds most likely via an X-philic attack of the P(III) nucleophile on the chalcogen of the P(V) species. For the transfer of oxygen, the reaction may also proceed via an edge attack on the P=O bond.