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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.
31

Development of Iron-Catalyzed C-N and C-C Bond Forming Reactions toward Functional Arylamine Synthesis / 機能性芳香族アミン類の合成を志向した鉄触媒炭素-窒素及び炭素-炭素結合生成反応の開発

Aoki, Yuma 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21780号 / 工博第4597号 / 新制||工||1716(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 中村 正治, 教授 大江 浩一, 教授 村田 靖次郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
32

Synthèse, marquage TEP et validation de nouveaux radiopharmaceutiques des récepteurs sérotoninergiques 5-HT6 et 5-HT7 / Synthesis, radiolabelling PET and validation of new radiopharmaceuticals of the serotonin receptors 5-HT6 and 5-HT7

Sagnes, Charlène 11 December 2009 (has links)
La sérotonine ou 5-hydroxytryptamine (5-HT) est un neurotransmetteur impliqué dans un grand nombre de fonctions physiologiques (thermorégulation, mémoire, sommeil, humeur…). La pluralité des troubles engendrés par un dysfonctionnement sérotoninergique s’explique par le grand nombre de récepteurs associés (5-HT1 à 5-HT7, eux-mêmes divisés en sous-groupes). Parmi eux, les récepteurs 5-HT6 et 5-HT7 sont les derniers à avoir été identifiés. A ce jour bien que leurs rôles biologiques restent méconnus, ils sembleraient être impliqués dans certaines pathologies psychiatriques (dépression, anxiété, schizophrénie…) et pourraient représenter de nouvelles cibles thérapeutiques. Ainsi, dans un premier temps, une étude bibliographique présentera l’ensemble des récepteurs sérotoninergiques et détaillera les travaux relatant des 5-HT6 et 5-HT7. La seconde partie sera consacrée à la synthèse de ligands potentiels des 5-HT7 et à l’étude de relation structure-activité associée. L’exemplification d’une réaction de C2-arylation d’indole inédite catalysée par le cuivre fera l’objet de la troisième partie. La quatrième partie sera consacrée à la synthèse de ligands antagonistes connus des récepteurs 5-HT6 afin de les employer comme radiotraceurs potentiels. Cette partie exposera également la synthèse de ligands potentiels inédits de ces récepteurs. Enfin, les premiers résultats de radiosynthèse et de leur application TEP (Tomographie à Emission de Positons) seront exposés / Serotonin or 5-hydroxytryptamine (5-HT) is a neurotransmitter involved in many physiological functions (thermoregulation, memory, sleep, mood ...). The plurality of disorders caused by a serotonergic dysfunction due to the large number of receptors involved (5-HT1 to 5-HT7, divided themselves into sub-groups). Among them, the 5-HT6 and 5-HT7 are the last to be identified. To date, although their biological roles remain unknown, they appear to be involved in some psychiatric disorders (depression, anxiety, schizophrenia ...) and could represent new therapeutic targets. Thus, initially, a bibliographic study will present all the serotonin receptors and detail work on the 5-HT6 and 5-HT7. The second part will be devoted to the synthesis of potential ligands of 5-HT7 and the study of structure-related activity. The exemplification of a reaction of C2-arylation of indole catalyzed by copper will be the third party. The fourth part will be devoted to the synthesis of antagonists ligands known of 5-HT6 receptors in order to use them as potential radiotracers. This part also describes the synthesis of novel potential ligands of these receptors. Finally, preliminary results of radiosynthesis and their application PET (Positron Emission Tomography) are exposed
33

Synthesis of pi conjugated polymers for use in photovoltaic and electrochromic applications

Deininger, James J. 21 September 2015 (has links)
Conjugated polymers are currently being used for a wide range of electronic applications. In this thesis, we studied two different synthetic approaches that lead to novel monomers and polymers that can be potentially used in electrochromic, or photovoltaic devices. The first approach described in this thesis is the utilization of olefin cross metathesis to create a family of dithienogermole (DTG) monomer derivatives in which synthetic control of the solubilizing side chains is achieved through an alkenyl building block. This alkenyl intermediate allows one to functionalize the DTG moiety though olefin cross metathesis to obtain a wide range of alkyl chain lengths and pendant functionalities on the polymer backbone. This work lead to the first example in the literature in which the synthesis of DTG moieties was not limited by the chain length of the solubilizing alkyl units. It provides a route that avoids the use of distillation for the purification the DTG monomer, allowing for the synthesis of a wide range of DTG derivatives that were previously unobtainable though the conventional synthetic methods. Finally, in this thesis we also describe the work of the use of direct (hetero)arylation polymerizations (DHAP) as a means of obtaining 3,4-propylenedioxythiophene-based conjugated polymers for use in electrochromic applications. This synthetic method offers a rapid route to achieving polymers in high yields with simplified purification procedures and low residual metal content, as determined by inductive coupled plasma-mass spectrometry (ICP-MS). The studied polymers possess comparable electrochromic properties to those previously reported by the Reynolds group, implying that their switching ability from a colored to a transmissive state is independent of the residual metallic impurities.
34

Arylation de nucléophiles catalysés par des complexes de cuivre / Copper catalysed arylation of nucleophiles

Tlili, Anis 05 December 2011 (has links)
Au cours de cette thèse, plusieurs nouvelles méthodes d'arylation de nucléophile (oxygéné, azoté et carboné) ont été mises au point ainsi qu'une étude mécanistique. Dans le cadre du projet ANR, nous avons réalisé des travaux dans ce domaine dans le laboratoire du Dr Anny Jutand à L'ENS Paris. D'un point de vue général, nous pouvons donc dire que nos méthodes se situent bien en phase avec les critères de la réglementation européenne visant à diminuer l'impact des produits chimiques sur l'environnement (REACH) par la recherche de nouvelles voies de synthèse moins toxiques et moins polluantes. Travaux en cours et perspectives : Par rapport aux réactions faisant intervenir des catalyseurs au palladium, celles impliquant le cuivre ont très peu été étudiées du point de vue de leur mécanisme. Les premiers travaux concernant le mécanisme de l'arylation de nucléophiles catalysé au cuivre ont débuté depuis seulement quelques années et ont conduit à environ une dizaine de publications. Malgré quelques avancées significatives, beaucoup reste à faire. / In this thesis, several new methods of nucleophilic arylation (oxygen, nitrogen and carbon) were developed and a mechanistic study. As part of the ANR project, we have carried out work in this field in the laboratory of Dr. Anny Jutand at ENS Paris. From a general point of view we can say that our methods are well in line with the requirements of European regulations to reduce the impact of environmental chemicals (REACH) by the search for new synthetic routes less toxic and less polluting. Work in Progress and prospects : Compared to reactions involving palladium catalysts, those involving copper have been studied very little in terms of their mechanism. Early work on the mechanism of arylation of nucleophiles catalyzed copper began last few years and led to about a dozen publications. Despite some significant advances, much remains to be done.
35

Synthèse et fonctionnalisation directe catalytique de la liaison C-H d'imidazolones : nouvel accès aux fluorophores analogues de la GFP / Synthesis and direct, catalytic functionalization of the C-H bond of imidazolones : novel access towards GFP-like fluorophores

Muselli, Mickaël 19 July 2017 (has links)
Les imidazolones sont des molécules étudiées de longue date, soit en tant que molécules bioactives, soit pour leurs propriétés de fluorescence, l'exemple le plus connu étant la GFP. De nombreuses synthèses étaient déjà décrites, en particulier la condensation d'une amine avec une oxazolone (méthode d'Erlenmeyer). Au cours de ce travail, nous avons non seulement amélioré le protocole d'Erlenmeyer, mais surtout développé une synthèse originale consistant à utiliser l'arylation C-H de 2-H imidazolones. Dans cet objectif, il a fallu tout d'abord mettre au point un protocole de synthèse des 2-H imidazolones, jusqu'alors très peu décrites, puis mettre au point les conditions d'arylation et de vinylation directe de ces molécules. Deux séries d'imidazolones ont été étudiées et publiées séparément : en premier lieu, les 4,4'-dialkyl-imidazolones, fréquemment employées pour leurs propriétés biologiques, puis, au cours du travail qui a suivi, l'arylation et la vinylation des 4- arylidène-2-H imidazolones. / Imidazolones have been studied for a long time, either as bioactive molecules or for their fluorescence properties, the best known example being the Green Fluorescent Protein or GFP. Numerous syntheses are already described, in particular the condensation of an amine with an oxazolone (Erlenmeyer method). In this work, we not only improved the condensation protocol but also developed an original synthesis consisting in using 2-H imidazolones CH arylation. To this end, it was first necessary to develop a protocol for the synthesis of 2-H imidazolones, hitherto very little described, and then to develop the conditions for arylation and direct vinylation of these molecules. Two sets of imidazolones have been studied and published separately: first, the 4,4'- dialkylimidazolones, frequently used for their biological properties, followed by arylation and vinylation of 4-arylidene-2-H imidazolones.
36

Palladation et fonctionnalisation de pyrimidinones et d'imidazolones / Palladation and functionalization of pyrimidinones and imidazolones

Collado Ruiz, Sandra 03 December 2018 (has links)
Depuis ces dix dernières années, notre laboratoire a développé une expertise dans le domaine de la fonctionnalisation de liaisons carbone-hydrogène (dite fonctionnalisation C-H) d’hétérocycles par catalyse aux métaux de transition. Le sujet de thèse s’inscrit dans un programme de recherche dirigé vers les hétérocycles pro-aromatiques à système N-acylamidine. Les travaux antérieurs ont porté sur les 4-alkyl et 4-arylidène imidazolones avec la production de nouvelles sondes GFP. Le présent travail de thèse vise à poursuivre le développement méthodologique en série pyrimidin-4-ones,encore très peu concernée dans ce domaine de recherche. Une méthode d’arylation C2-H de lapyrimidin-4-one substituée sur l’atome d’azote par divers chélates directeurs a été mise au point en utilisant une catalyse coopérative Pd(0)-Cu(I) et des halogénures d’aryles comme partenaires de couplage. L’étendue de la réactivité a été examinée de façon exhaustive puis la méthodologie a été évaluée pour l’arylation C2-H d’analogues structurels fonctionnalisés en positions C5. Une seconde étude s’inscrit dans le projet de rigidification des sondes GFP à coeur 4-arylidène imidazolone. Un travail préliminaire d’ortho-palladation C-H a été effectué en collaboration avec le Dr Esteban Urriolabeitia de l’université de Saragosse en Espagne. Les propriétés photophysiques des palladacycles originaux ainsi préparés ont été déterminées et leurs réactivités aux agents de couplage et aux oxydants évaluées. / Since past decade, our laboratory is concerned with transition-metal catalyzed C-H functionalization of heterocycles. A recent research program is dedicated to the class of N-acyl amidine pro-aromatic heterocycles. This present thesis work is first directed to the pyrimidin-4-one series that remains highly sparsely evaluated. As main results, Pd(0)-catalyzed and Cu(I)-assisted C2-H arylation of pyrimidin-4-one flanked with picolinyl and other ortho-directed groups at the nitrogen atom was set up using arylhalides as coupling partners. The C5-substituted pyrimidin-4-ones were also evaluated. To pursue recent investigations in 4-alkyl and 4-arylidene imidazolone series leaing ding to innovative GFP probes, the second work aims at evaluating the first step of an ultimate intramolecular C-H/C-H coupling to stiffen the 4-arylidene imidazolone core. For that, the intramolecular ortho-palladation was achieved in collaboration with Dr. Esteban Urriolabeitia of the University of Zaragoza in Spain providing a broad panel of original imidazolone-based palladacycles. Their photophysical properties were determined and their reactivity towards cross-coupling as well as oxidating agents were also evaluated.
37

Přímá arylace a její využití při přípravě supramolekulárních polymerů / Direct arylation and its application in supramolecular polymer synthesis

Loukotová, Lenka January 2014 (has links)
This thesis is divided into two parts. In the first part there is reported palladium- catalysed regioselective direct arylation of benzofurans with arylsulfonyl chlorides as the coupling partner to C2 carbon. The best reaction conditions of this reaction were investigated, then the influence of various arylsulfonyl chloride substituents to the reaction and finally it is reported direct arylation of C2-arylated benzofuran to C3 carbon to give diarylated benzofuran with different aryl substituents. In the second part, there is reported the synthesis of 2-(hydroxymethyl)-5,7-bis{5- [(2,2':6',2''-terpyridine)-4'-yl]thiophen-2-yl}-2,3-dihydrothieno[3,4-b][1,4]dioxin and modification of its sidechain. As a starting material of the synthesis it was used commercially available 4'-bromo-(2,2':6',2''-terpyridine). The synthetic sub-steps included Suzuki cross- coupling, bromination and C-H bond activation. Then it was also reported the complexation of synthesized oligomer with zinc and iron cations.
38

Arylation migratoire C(sp3)-H d'énolates d'esters / Migrative C(sp3)-H arylation of ester enolates

Aspin, Samuel 16 December 2013 (has links)
La fonctionnalisation C(sp3)-H catalysée par des métaux de transitions, ouvre de nombreuses perspectives en synthèse organique, permettant des voies d'accès plus économes en atomes, et en étapes à des molécules à forte valeur ajoutée. Dans cette optique, une méthode efficace permettant l'arylation des liaisons C(sp3)-H en position α d'un groupement attracteur, plus communément appelée α -arylation a récemment fait l'objet d'une attention toute particulière de la part de la communauté scientifique. Le travail détaillé dans ce manuscrit décrit les dernières avancées de cette méthodologie, ainsi qu'une variante «β-arylation » développée au laboratoire qui constitue une évolution significative dans le domaine de l'arylation regiosélective des liaisons C(sp3)-H non activées. Dans le cadre de ce projet de thèse nous nous sommes efforcés de développer cette nouvelle réaction que nous avons pu optimiser pour l'étendre à une famille plus étendue de substrats de type amino-esters. Dans la continuité de ce travail nous avons réalisé la première réaction d'arylation migratoire sélective d'amino-esters pouvant aller jusqu'à la position η d'une chaîne alkyle linéaire. Enfin, dans le but d'accéder à de nouvelles molécules à plus haute valeur ajoutée, nous avons pu appliquer notre méthodologie aux acetals de cétènes silylés permettant de dépasser certaines limitations du système existant. Dans ce cas précis, des conditions plus douces (sans base forte) ont permis l'arylation de substrats dits sensibles et par extension la synthèse de lactones fonctionnalisées / The transition metal catalysed functionalization of C(sp3)-H bonds unlocks numerous perspectives within organic synthesis in terms of atom economical access routes to otherwise difficult to synthesise molecules. One efficient method to exact such transformations involves the exploitation of an activated C-H bond situated adjacent to an activating electron withdrawing group, allowing facile insertion of a transition metal catalyst species and subsequent functionalization with a new species (normally an aryl group). This strategy is generally termed ‘α-functionalization’. The work detailed within this manuscript describes a diversion from the classic, and well documented α-functionalization reaction, in which rearrangement steps within the catalytic cycle give rise to β- and more remote substrate functionalization. The first new methodology to be described involves a fundamental extension to the in-house developed β-arylation reaction, in which, through careful substrate and ligand choice, this methodology could be applied to achieve the functionalization of simple ester enolates in remote γ- to η - positions. The developed strategy allowed the synthesis of a small range of interesting homophenylalanine analogues, and higher homologues. The second methodology to be described involves a necessary modified protocol for the β-arylation reaction, in which silyl ketene acetals were exploited as mild metal-enolate surrogates, allowing the coupling of base-sensitive substrates. The previously described reaction scope has been extended in terms of both the electrophile and nucleophile coupling partners through the development of mild reaction conditions, which subsequently allowed application of several products towards the synthesis of lactones
39

Metalated Nitriles: Ligand Exchange and Copper-Catalyzed Reactions

Nath, Dinesh 17 April 2015 (has links)
This thesis describes new methods of carbon-carbon bond formation using metalated nitriles generated via metal exchange reactions. Sulfinylnitriles undergo a sulfinyl-metal exchange to yield lithiated, magnesiated and zincated nitriles, which can trap a range of electrophiles. The sulfinyl-metal exchange is effective with vinylic, quaternary and tertiary substitution patterns and addresses the long-standing problem of alkylating secondary nitriles. This method was then further extended to other oxidation states of sulfur, namely sulfonyl-metal exchange and relatively unknown sulfide-metal exchange. The sulfide metal exchange overcomes the problem related to the propensity of highly substituted sulfinylnitriles to eliminate. Sulfide-metal exchange is synthetically attractive because of the numerous methods for generating arylsulfides and the high tolerance of arylsulfides to numerous reagents. <br>A copper-catalyzed arylation reaction of aryl iodides and metalated nitriles was developed using catalytic Cu (I) and an amine ligand. A proof of principle has been established, providing a sound basis for developing the reaction. A new strategy has been developed for alkylation of alkenenitrile using LDA as base in presence of catalytic CuCN. Subsequent trapping with an electrophile, affords alkylated alkenenitriles in which the olefin is no longer in conjugation with the nitrile. <br>The distinct structural differences between N- & C-metalated nitriles have been harnessed in a series of chemoselective alkylations. Lithiated nitriles are found to be particularly reactive toward alkyl halides whereas magnesiated nitriles react selectively with oxygenated electrophiles. Using this strategy allows chemoselective alkylation of metalated nitriles. / Bayer School of Natural and Environmental Sciences; / Chemistry and Biochemistry / PhD; / Dissertation;
40

Studies on the Mechanism of Direct Arylation of Pyridine N oxides: Evidence for the Essential Involvement of Acetate from the Pd(OAc)2 Pre-Catalyst at the C-H Bond Cleaving Step

Sun, Ho-Yan 08 February 2011 (has links)
Detailed mechanistic studies on the palladium-catalyzed direct arylation of pyridine N-oxides are presented. The order of each reaction component is determined to provide a general mechanistic picture. The C-H bond cleaving step is examined in further detail through computational studies, and the calculated results are in support of an inner-sphere concerted metallation-deprotonation (CMD) pathway. Competition experiments were conducted using N-oxides of varying electronic characters, and results revealed an enhancement of rate when using a more electron-deficient species which is in support of a CMD transition state. The effect of base on reaction rate was also examined and it was found that a carboxylate base was required for the reaction to proceed. This led to the conclusion that Pd(OAc)2 plays a pivotal role in the reaction mechanism as more than merely a pre-catalyst, but as a source of acetate base required for the C-H bond cleavage step.

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