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Tetraamido- (TAML) and tetraaza- (cyclam) metallo-complexes as mild catalysts for the sustainable oxidation of alcohols / Tetraamido- (TAML) et tetraaza- (cyclam) metallo-complexes en tant que catalyseurs doux pour l'oxydation durable d'alcoolsZhang, Zhan 20 December 2018 (has links)
De nombreux complexes de Fe(TAML) ont été décrits au cours des dernières années. Notre groupe a étudié l’utilisation du complexe Fe(TAML-Me2) pour l’oxydation de liaisons C-H benzyliques. L'un des objectifs de cette thèse était de fonctionnaliser le complexe Fe (TAML-Me2) à différentes fins.L'une des fonctionnalisations consistait à utiliser un triazole substitué par une chaîne hexyle, qui pourrait influencer les propriétés physicochimiques du complexe de fer et qui pourraient être utilisées en catalyse homogène. Inversement, un TAML fonctionnalise par 1 triethoxysilane a été conçu pour être greffé sur un support inorganique pour une utilisation ultérieure en catalyse hétérogène. Enfin, une fonctionnalisation par une queue fluorée devai permettre était d'augmenter la solubilité du complexe dans les solvants fluorés en vue d'une utilisation potentielle dans un mélange biphasique susceptible de favoriser la recyclabilité du catalyseur.Nous avons révélé que le complexe MnII (Me2EBC)Cl2 pouvait catalyser l'oxydation d'une série d'alcools benzyliques et aliphatiques avec H2O2. Les conversions des alcools en composés carbonylés correspondants ont atteint 98% avec une sélectivité bonne à excellente / Fe(TAML) complexes have been investigated a lot in recent years. Our group has investigated the simplest Fe(TAML) catalyst for its oxidation with high efficiency. The purpose of this thesis was to functionalize the complex Fe(TAML-Me2) for different uses.One of the functionalizations was to have a hexyl-substituted triazole “tail”, which could influence the physicochemical properties of the iron complex in homogeneous catalysis. Conversely, a silicon tailed-one was designed to be grafted on an inorganic support for a use in heterogeneous catalysis. At last, the purpose of the fluorinated tail was to increase the solubility of the metallocomplex in fluorinated solvents for a potential use in a biphasic mixture that could favor the recyclability of the catalyst. The other purpose of the thesis was to develop an environmental benign catalytic oxidation system with a bioinspired catalyst MnII(Me2EBC)Cl2. We disclosed that the MnII(Me2EBC)Cl2 complex could catalyze the oxidation of a series of benzylic and aliphatic alcohols with H2O2. Conversions of the alcohols to corresponding carbonyl compounds reached 98% with good to excellent selectivity
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Développement de nouveaux catalyseurs pour la dépolymérisation de la lignine par voie d’oxydation / Design of new catalysts for lignin depolymerisation via oxidationKieffer, Raphaëlle 25 September 2015 (has links)
La lignine est l'un des biopolymères les plus importants sur Terre. Elle est extraite des plantes et représente la plus grande source de noyaux aromatiques dans la biomasse. De nombreux projets ayant pour but la dépolymérisation de la lignine en molécules de faibles poids moléculaires, valorisables par les industries chimiques, sont de plus en plus développés au vu du fort potentiel de cette bio-ressource. Le but de notre projet était de développer un nouveau système catalytique pour la dépolymérisation de la lignine. Nous nous sommes intéressés à la conception de nouveaux catalyseurs homogènes et hétérogènes, basés sur la structure connue du complexe Fe(TAML). Nous avons étudié leurs réactivité et stabilité en conditions de catalyse oxydante, et les avons comparés aux caractéristiques du Fe(TAML) existant. Pour ce faire, l'étude catalytique a été réalisée sur des molécules modèles de la lignine, dans le but d'éviter les problèmes analytiques liés à la structure du polymère. Dans un premier temps, nous présenterons la stratégie de fonctionnalisation du ligand TAML connu afin d'obtenir de nouveaux complexes qui puissent être greffés sur un support de silice. Dans un deuxième temps, nous parlerons des résultats de la catalyse oxydante en conditions homogènes et hétérogènes, et de l'influence du changement de la structure des ligands sur l'activité des catalyseurs / Lignin is one of the most abundant biopolymers on earth. It is issued from plants and represents the largest source of aromatics in biomass. Projects aiming at depolymerizing lignin to obtain value-added small molecules for the chemical industry are more and more developed due to the high potential of this bio-resource. The goal of our project was to develop a new catalytic system for the depolymerization of lignin. We have been interested in designing new homogeneous and heterogeneous catalysts based on the known structure of the Fe(TAML) complex. We have studied their reactivity and stability under oxidative catalysis conditions, and have compared them to the characteristics of the existing Fe(TAML). To do so, the catalysis study has been realized on lignin small model molecules to avoid the analytical problems related to a polymer backbone. In a first hand, we will present the strategy of functionalization of the known TAML ligand to design new complexes to be grafted on a silica support. In a second hand, we will talk about the results of oxidative catalysis in homogeneous and heterogeneous conditions, and the influence of the ligand structure change on the activity of the catalysts
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Quantifying the Effects of a TAML Catalyst and Two Positive Controls on the Male Mouse Mammary Gland After Exposure During Development or in AdulthoodSzabo, Gillian K 28 June 2022 (has links)
Estrogenic chemicals are common pollutants in wastewater and current methods used in wastewater treatment processes are not typically effective in removing these compounds. Thus, many estrogenic chemicals, as well as other pharmaceuticals, are detected in drinking water supplies, contributing to human exposures. This concerning public health situation has led some green chemists to investigate the feasibility and efficacy of tetra-amido macrocyclic ligands (TAML), which have been proposed to be environmentally friendly catalysts that can be used to treat wastewater. TAML works by catalyzing the oxidation of micropollutants, breaking pollutants down into substances that can be assimilated by bacteria. These breakdown products are anticipated to no longer pose an environmental or health concern. Prior to their use in environmental matrices, TAML must first be evaluated to ensure that these compounds pose a low environmental and human-health hazard. Here, we exposed adult female mice to one of three doses of New-TAML 7 (NT7), or an estrogen receptor agonist (ethinyl estradiol, EE2) or an androgen receptor antagonist (flutamide), for two weeks prior to mating, throughout pregnancy, and throughout the lactational period. Male mice used for breeding purposes, the F0 males, were also exposed to the drinking water during the 2-week mating period. Following this acute exposure, the F0 males were necropsied and evaluated for signs of overt toxicity and repro-endocrine disruption. There was a statistically significant decrease in the F0 males spleen weight. Male offspring, the F1 generation, were evaluated at weaning (postnatal day 21), in puberty (postnatal day 32), and in adulthood. We first evaluated organs known to be sensitive to toxic effects. In male mice developmentally exposed, we have discovered that all treatments decreased spleen size at postnatal day (PND) 21 but not in early adulthood. At PND 16, no significant effects were observed. At PND21, no effects were observed on the weight of the kidney, liver, testes, or seminal vesicles; however, spleen weight was significantly decreased in the positive controls and the mid-NT7 group. In early adulthood, no effects have been observed on organ weights of the flutamide group; however, the size of both testes is significantly affected by the mid-NT7 dose and the EE2 treatment. By six months of age, there were no statistically significant effects, although this is likely in part due to inadequate statistical power. We also evaluated the effect of NT7, EE2, and flutamide on the male mouse mammary gland. Because of the conserved role hormones play in mouse development, a mammary gland is a valuable tool for identifying endocrine disruptors. We found that EE2 increased the size and number of branching points starting at PND21 and continuing until nine weeks of age. TAML had little effect on the morphology of the male mammary gland, with the exception of increased ductal branching at PND21. This, along with the change in testes weight, may suggest TAML can affect estrogen-mediated outcomes; many of our observed effects warrant additional study.
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