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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Synthèse et coordination de dérivés calixarène et de thiacalixarène en conformation 1,3-alternée / Synthesis and coordination of calixarene and thiacalixarene derivatives in 1,3-alternate conformation

Noamane, Mohamed Habib 13 December 2013 (has links)
Les récepteurs moléculaires sont des architectures maintenues par des liaisons covalentes et capables de fixer sélectivement des substances (ioniques et/ou moléculaires) au moyen d’interactions intermoléculaires diverses, aboutissant ainsi à la formation d’un assemblage d’au moins de deux espèces nommé complexe moléculaire. Au cours de ce travail, des stratégies de synthèse de dérivés de calix[4]arène et de son analogue thiacalix[4]arène en conformation 1,3-alternée ont été mises au point. Ces composés ont été fonctionnalisés par des groupements pyridine, catéchol, imidazole, pyrazole et pour la première fois oxamate. Les composés obtenus ont été caractérisés à la fois en solution par RMN et à l’état cristallin. Les propriétés complexantes vis-à-vis des métaux de transition en solution sont présentées. Pour certains dérivés, le pouvoir extractant envers les métaux de transition a été étudié et discuté. Enfin, la formation de réseaux de coordination à l’état cristallin par auto-assemblage de dérivés de calixarène ou de thiacalixarène et le cation argent est présentée et commentée. / Molecular receptors are preorganised architectures held by covalent bonds and capable of binding selectively ionic and / or molecular substrates via various intermolecular interactions, leading to the formation of molecular complexes composed of at least two species.In this work, the synthesis of a library of calix[4]arene and its analogue thiacalix[4]arene in 1,3-alternate conformation based ligands and tectons has been investigated. These two types of platforms have been equipped with pyridine, catechol, imidazole, pyrazole and, for the first time, oxamate units as coordinating sites. All compounds prepared were characterized in solution and in some cases in the crystalline state. Their binding propensity in solution towards transition metals has been determined and discussed. For some derivatives, their metal extracting properties have been investigated and presented. Finally, the formation of extended periodic architectures of the coordination network type in the crystalline state by self-assembly of calixarene based tectons and silver cation was achieved and presented.
42

d10-Metallkomplexe des p-tert-Butyltetramercaptotetrathiacalix[4]arens

Frank, Nicolas 08 October 2020 (has links)
Ziel dieser Arbeit war es, das Potenzial von p-tert-Butyltetramercaptotetrathiacalix[4]aren (H4(MTC[4])) zum Aufbau von mehrkernigen Komplexen mit weichen Metallionen mit d10-Elektronenkonfiguration zu untersuchen. H4(MTC[4]) bietet im Vergleich zum bekannteren p-tert-Butylcalix[4]aren erweiterte Bindungsmöglichkeiten für Metallionen an den Thioetherbrücken. Die Funktion der Metallionen Cu(I) und Zn(II) in biologischen Systemen lieferte die anfängliche Inspiration, jedoch erschien auch die Untersuchung anderer Metalle wie Nickel, Silber und Gold in Verbindung mit (MTC[4])4- Liganden lohnenswert, da diese Metalle durch ihre jeweils bevorzugten Koordinationsgeometrien neue Strukturen und Koordinationsmöglichkeiten an H4(MTC[4]) aufzeigen könnten. In Experimenten mit Kupfer(I)-Ionen konnten der Kupferkomplex [(Ph3PCu)4(MTC[4])] sowie das Hexamer [Cu4(MTC[4])]6 hergestellt und charakterisiert werden. [Cu4(MTC[4])]6 weist eine einzigartige, supramolekulare, hohle Cu24S48-Käfigstruktur auf. Die [Cu4(MTC[4])]-Einheiten werden durch Cu2S2-Motive verknüpft, die extrem kurze Cu···Cu-Abstände aufweisen. Durch NMR-Experimente wurde gezeigt, dass die Hohlräume von [Cu4(MTC[4])]6 in Lösung Acetonitril und Methan aufnehmen können. In Experimenten mit Silber(I)-Ionen wurden die Molekülstrukturen der Silberkomplexe [(Ph3PAg)2AgH(MTC[4])], [(Ph3PAg)4AgCl(MTC[4])] und [(Ph3PAg)4(MTC[4])] bestimmt. Diese zeigen, dass H4(MTC[4]) gegenüber Silber- und Kupferionen ein ähnliches Koordinationsverhalten aufweist. In Experimenten mit Gold(I)-vorläufern war es möglich, zu steuern, wie viele Metallionen ein einzelnes Molekül H4(MTC[4]) koordiniert. Die Komplexe [(Ph3PAu)2H2(MTC[4])], [(Me3PAu)3H(MTC[4])] und [(Me3PAu)4TlCl(MTC[4])] wurden synthetisiert. Diese bieten teilweise durch vorhandene freie Thiolfunktionen Potenzial für die Synthese heterometallischer Komplexe. / It was the aim of this work, to assess the potential of p-tert-Butyltetramercaptotetrathiacalix[4]arene (H4(MTC[4])) to create multinuclear complexes with soft metal ions of d10 electron configuration. In contrast to the more known p-tert-Butylcalix[4]aren, H4(MTC[4]) offers extended possibilities for the coordination of metal ions at the thioether groups. While this work was initially inspired by the function of Cu(I) and Zn(II) ions in biological systems, the metal ions, which were incorporated into the Calixarene, were soon expanded by Ni(II), Ag(I) and Au(I) ions. Through their different preferred coordination geometries, these metal ions could yield new information about coordination modes of H4(MTC[4]). In experiments with copper(I) ions the complex [(Ph3PCu)4(MTC[4])] and the hexamer [Cu4(MTC[4])]6 were synthesized and characterized. [Cu4(MTC[4])]6 consists of a unique, supramolecular hollow Cu24S48 cage structure. The [Cu4(MTC[4])] units are connected by Cu2S2 motivs, which display extraordinary short Cu···Cu distances. An investigation by NMR spectroscopy indicated that the cavities of [Cu4(MTC[4])] in solution can hold acetonitrile or methane molecules. In experiments with silver(I) ions, the molecular structures of the compounds [(Ph3PAg)2AgH(MTC[4])], [(Ph3PAg)4AgCl(MTC[4])] and [(Ph3PAg)4(MTC[4])] were determined. In these compounds H4(MTC[4]) exhibits a similar coordination behaviour towards Ag(I) ions as it does towards Cu(I) ions. In experiments with gold(I) precursors it was possible to control how many gold(I) ions were coordinated by H4(MTC[4]). The complexes [(Ph3PAu)2H2(MTC[4])], [(Me3PAu)3H(MTC[4])] and [(Me3PAu)4TlCl(MTC[4])] were synthesized and studied. Due to their free thiol functions, they are potential precursors for the synthesis of heterometallic complexes.

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