Dissertations / Theses on the topic 'Carboxy Pyridine'
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Leyva-Ramos, Roberto, Raul Ocampo-Perez, Oliva L. Torres-Rivera, Maria S. Berber-Mendoza, and Nahum A. Medellin-Castillo. "Kinetics of pyridine adsorption onto granular activated carbon." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-191056.
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Leyva-Ramos, Roberto, Raul Ocampo-Perez, Oliva L. Torres-Rivera, Maria S. Berber-Mendoza, and Nahum A. Medellin-Castillo. "Kinetics of pyridine adsorption onto granular activated carbon." Diffusion fundamentals 11 (2009) 83, S. 1-2, 2009. https://ul.qucosa.de/id/qucosa%3A14054.
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Robveille, Jacques. "Synthèse de pyridine et d'isoquinoléine marquées au 14C sur l'hétérocycle azoté." Lyon 1, 1985. http://www.theses.fr/1985LYO10513.
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Trois procedes de synthese differents : la pyridine et les pyridines mono-2 et disubstituees-2,6 marquees c14 sont preparees a partir de composes marques dioxo-1,5 par cyclisation de leurs dioximes ; les pyridines substituees en 3 marquees c14 sont preparees par cyclisation thermique d'isocyanates de butadienyle prepares a partir des acides pentadiene-2,4oiques marques c14 ; les furo-, thieno- et pyrrolo (3,2-c) pyridines marquees c14 sont preparees a partir des acides furanne-, thiophene- et pyrroleacryliques-2 marques via les isocyanates. Application a la synthese d'isoquinoleines marques c14 a partir d'acides cinnamiques
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Bonnet, Véronique. "Synthèse et réactivité d'organomagnésiens en série pyridinique." Rouen, 2002. http://www.theses.fr/2002ROUES013.
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Plusieurs méthodes de préparation via des magnésiens pyridiniques ont été développées pour accéder à de nombreux composés. L'échange halogène-magnésium a été étudié à partir de nombreuses bromopyridines. Cette réaction menée à température ambiante avec le chlorure d'isopropylmagnésium a conduit aux chlorures de pyridylmagnésium correspondants, qui ont été piégés par différents électrophiles. La métallation dirigée par un groupement carboxamide secondaire ou pivaloylamino en position 2, a conduit, en utilisant deux bases magnésiées, à des halogénures de 3-pyridylmagnésiums qui ont alors été piégés par différents électrophiles. Des magnésiens benzéniques et pyridiniques ont été engagés dans des couplages catalysés par des métaux de transition avec de nombreux substrats aromatiques p-déficitaires azotés. La réaction a pu être menée à basse température, permettant ainsi l'utilisation de substrats sensibles aux additions nucléophiles ou porteurs de fonctions réactivesSeveral synthetic methods via magnesiated pyridines were developed to reach many compounds. The halogen-magnesium exchange was developed from many easily available bromopyridines. This reaction when proceeded at room temperature with isopropylmagnesium chloride gave the corresponding pyridylmagnesium chlorides, which could be trapped with various electrophiles. The metallation using isopropylmagnesium chloride or dibutylmagnesium as bases, directed by a secondary carboxamide or a pivaloylamino group at C2 led to 3-pyridylmagnesium halides, which were quenched by different electrophiles. At last, magnesiated benzenes and pyridines were involved in transition metals catalyzed couplings with many nitrogen p-deficient aromatic substrates. The reaction could proceed at low temperatures, allowing the use of substrates prone to nucleophilic attack or carrying reactive functions
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鄭嘉慧 and Kar-wai Anita Cheng. "Preparation, reactivities and oxidative catalytic activities of ruthenium(II) polypyridines, rhenium(I) carbonyl complexes andruthenium-encapsulated meso- and micro-porous molecular sieves." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31236662.
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Cheng, Kar-wai Anita. "Preparation, reactivities and oxidative catalytic activities of ruthenium(II) polypyridines, rhenium(I) carbonyl complexes and ruthenium-encapsulated meso- and micro-porous molecular sieves /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1973816X.
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Boucida, Seddik. "Synthèse et étude de cyclotriphosphazènes à liaisons phosphore-carbone porteurs de substituants pyridyle." Montpellier 2, 1998. http://www.theses.fr/1998MON20209.
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Dans le but d'acceder a des cyclotriphosphazenes porteurs d'heterocycles azotes par l'intermediaire de liaisons phosphore-carbone, deux voies de synthese ayant pour precurseur commun le n, n-diethyl di(3-pyridyl)phosphinamide ont ete suivies. Elles ont conduit, d'une part a l'hexa (3-pyridyl)cyclotriphosphazene et d'autre part, au n, n-diethyl 4, 4-bipyridyl-3, 3-ylene phosphinamide. L'hexa(3-pyridyl)cyclotriphosphazene a ete synthetise en cinq etapes en generalisant une suite de reactions deja mises au point lors de travaux anterieurs. Le n, n-diethyl 4, 4-bipyridyl-3, 3-ylene phosphinamide a, quant a lui, ete prepare en utilisant une voie d'acces inedite par ortholithiation et cylisation one pot du n, n-diethyl di(3-pyridyl)phosphinamide. Par hydrolyse acide de ce phosphinamide cyclique, l'acide 4, 4-bipyridyl-3, 3-ylene phosphinique a ete obtenu de maniere quantitative. Cet acide devrait permettre d'acceder au cyclotriphosphazene spiranique correspondant. Une etude systematique d'optimisation a ete entreprise pour la synthese du n, n-diethyl di(3-pyridyl)phosphinamide par voie organolithienne. Le meilleur taux de formation obtenu est de 42% et le meilleur rendement est de 30%. Une etude comparative a ete menee sur quelques proprietes chimiques et physicochimiques de l'hexa(2-pyridyl)cyclotriphosphazene et de l'hexa(3-pyridyl)cyclotriphosphazene (etudes de structures par diffraction des rayons x, complexation metallique, etudes rmn #3#1p, #1#3c et #1h). Les premiers resultats paraissent privilegier l'hexa(2-pyridyl)cyclotriphosphazene comme eventuel precurseur de materiau a proprietes electriques.
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Couve-Bonnaire, Samuel Castanet Yves Carpentier Jean-François. "Synthèse de dérivés pyridiniques fonctionnalisés-cétones, cétoamides et cétoesters-par réaction de carbonylation de précurseurs halogènes." [S.l.] : [s.n.], 2001. http://www.univ-lille1.fr/bustl-grisemine/pdf/extheses/50376-2001-163-164.pdf.
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Couve-Bonnaire, Samuel. "Synthèse de dérivés pyridiniques fonctionnalisés-cétones, cétoamides et cétoesters-par réaction de carbonylation de précurseurs halogènes." Lille 1, 2001. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2001/50376-2001-163-164.pdf.
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La pyridine et ses dérivées jouent un rôle majeur en chimie hétérocyclique de part leur vaste panoplie de potentialités chimiques et biologiques liées à la présence de l'hétéroatome d'azote. A partir de précurseurs halogénés aisément accessibles, deux nouvelles méthodes de synthèse de dérivés pyridiniques fonctionnalisés, catalysés au palladium, ont été développées. Elles conduisent respectivement à des aroylpyridines et des dérivés d'acides pyridylglyoxyliques qui s'avèrent être des intermédiaires potentiels dans la synthèse de nombreuses molécules d'intérêt pharmaceutique ou agrochimique. La première réaction étudiée est une réaction de couplage de substrat pyridinique avec un acide arylboronique sous monoxyde de carbone ; elle dérive de la réaction de Suzuki. L'influence sur la réaction de nombreux facteurs expérimentaux a été examinée. Les plus importants sont la pression de CO, la nature du précurseur catalytique et la nature du motif halogéné présent sur la pyridine. La réaction s'est révélée efficace avec des rendements isolés supérieurs à 80% et des sélectivités en cétones supérieures à 90%. La deuxième méthode de fonctionnalisation met en jeu la réaction de double carbonylation d'iodopyridines conduisant à des composés alpha-cétoamides et alpha-cétoestersUne fois encore, les résultats dépendent des paramètres expérimentaux et plus particulièrement de la nature du précurseur catalytique et de la position du motif halogéné sur le cycle hétéroaromatique. Les meilleurs résultats sont obtenus en synthèse d'alpha-cétoamides, néanmoins les séléctivités en composé dicarbonylé, cétoamides ou coesters, sont les plus élevées rapportées pour ce type de composés. La dernière partie de nos travaux est consacrée à la réduction asymétrique des dérivés d'acides pyridyglyoxyliques synthétisés précédemment par deux méthodes différentes : l'hydrogénation asymétrique et la réduction par agent stoechiométrique. L'influence néfaste du noyau pyridinique sur la réaction a été évaluée
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Roudesly, Fares. "Fonctionnalisation C-H dirigée d'hétérocycles azotés." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS354.
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Ce travail de thèse a apporté sa contribution et de nouvelles connaissances dans le domaine de l’activation / fonctionnalisation C-H de noyaux azotés de type pyridine et pyrrole. D’abord, nous avons développé une méthode permettant l’allylation et l’oléfination régiosélective d’azines N-oxyde en utilisant un complexe de Pd(0) formé in situ. Le champ d’application de cette réactivité a ensuite été étudié. Des études expérimentales et des calculs DFT nous ont permis de proposer un mécanisme pour les étapes d’allylation et d’isomérisation. Nous proposons que l’étape d’activation C-H est l’étape cinétiquement déterminante du cycle catalytique et se fait selon un mécanisme de déprotonation/palladation par sphère externe. Ensuite, nous nous sommes intéressés à l’application de la réaction de Murai aux dérivés du 2- pyrrole carboxaldéhyde en utilisant un complexe de Ru(0). L’utilisation du monoxyde de carbone sous pression atmosphérique nous a permis d’obtenir les produits d’acylation en présence de différents vinylsilanes et styrènes. L’application de cette réactivité à d’autres dérivés du 2-pyrrole carboxaldéhyde est en cours d’étude au laboratoireThis thesis work has brought its contribution the field of C-H activation / functionalization of nitrogenous containing rings as pyridine and pyrrole. First, we developed a strategy for a Pd- catalyzed regioselective allylation and alkenylation of azine N-oxides. The scope of this reactivity has been studied. Experimental studies and DFT calculations allowed us to propose a mechanism for the allylation and isomerization steps. We propose that the C-H activation step is the rate determining step of the catalytic cycle, and that it takes place through an outer sphere deprotonation / palladation mechanism. Next, we applied the Murai reaction to 2-pyrrole- carboxaldehyde derivatives using a Ru(0) complex. Under an atmospheric pressure of carbon monoxide, we could obtain the acylated products in the presence of various vinylsilanes and styrenes. The application of this reactivity to other 2-pyrrole carboxaldehyde derivatives is under study in the laboratory
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Guetta, Brigitte. "Vieillissement hygrothermique de composites a matrice psp : etude cinetique, mecanique et spectroscopique." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0057.
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Pittaya, Kanchanapakonchai Amnuay Thithapandha. "Effects of vitamin B6 on CC14 toxicities in rats /." abstract, 1986. http://mulinet3.li.mahidol.ac.th/thesis/2529/29E-Pittaya-K.pdf.
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Leclerc, Hervé. "Caractérisation par spectroscopie infrarouge de solides organiques inorganiques de type MOF (Metal Organic Framework) : Thèse soutenue sur un ensemble de travaux." Caen, 2011. http://www.theses.fr/2011CAEN2017.
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Ce travail rapporte la caractérisation par spectroscopie infrarouge in situ d’une famille iso-structurale de quatre solides poreux organiques-inorganiques de type MOF (MOF : Metal Organic Framework) dénommés MIL-100(X) (MIL pour Matériaux de l’Institut Lavoisier) avec X= Al3+, Fe3+, Al3+ et V3+. Les caractérisations des centres métalliques et des propriétés acido-basiques ont été réalisées pour différentes températures d’activation des matériaux par ajouts ou non de molécules sondes telles que CO, CO2, CD3CN, pyridine et propyne. La première partie, portant sur l’étude du MIL-100(Cr), révèle l’absence de sites basiques de force notable, mais la présence de centres acides de Lewis Cr3+ localisés sur les trimères. L’adsorption d’eau ou d’alcools transforme ces sites en sites acides Bronsted dont la force dépend de la nature de l’adsorbat et du complexe formé. La deuxième partie est consacrée à l’étude du MIL-100(Fe). Elle révèle d’abord l’existence de sites Fe3+ susceptibles de se réduire en sites Fe2+ par chauffage sous vide, puis démontre l’existence d’un phénomène de rétrodonation qui accroit les interactions entre les sites Fe2+ insaturés et des molécules telles que le CO, le propène et le propyne. L’étude spectroscopique du MIL-100(Al), présentée en troisième partie, rapporte pour la première fois une caractérisation fine de sites Al3+ insaturés en conformation pentaédrique et présents en grande quantité dans un environnement cristallographique bien défini. Le dernier chapitre présente une caractérisation du MIL-100(V) pour différentes température d’activation : nature des espèces extra réseaux et des centres métalliques insaturésThis study reports the characterization by in situ infrared spectroscopy of an isostructural family of four porous MOFs (MOF: Metal Organic Framework) denoted MIL-100(X) (MIL: Material from the Institute Lavoisier) with X: Al3+, Fe3+, Al3+ and V3+. The characterizations of the metallic centers and acido-basic properties have been performed at different temperature of activation by adsorption or not of probe molecules such as CO, CO2, CD3CN, pyridine and propyne. The first part devoted to the MIL-100(Cr), reveals the lack of any significant basic sites but the occurrence of Cr3+ Lewis acid sites located on the trimers. Adsorption of water or alcohols transforms the Lewis sites into Bronsted acid sites whose strength depends on the nature of the adsorbate and of the complex formed. The second part is dedicated to the study of the MIL-100(Fe) material. It reveals first the presence of Fe3+ sites able to be reduced into Fe2+ sites by thermal treatment under vacuum and secondly demonstrates the occurrence of a pi-back donation effect which increases the interactions between Fe2+ unsaturated sites and molecules such as CO, propene and propyne. The spectroscopic study of MIL-100(Al) presented in the third part reports for the first time a precise characterization of unsaturated pentahedral Al3+ sites present in a large amount and in a well defined crystallographic environment. The last chapter presents the characterization of MIL-100(V) activated at different temperatures: nature of the extra framework species and of unsaturated metallic sites
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Perez, Natália Marcomini. "Investigação da influência do solvente nas transições eletrônicas e na liberação de CO de carboxilatos trinucleares de rutênio." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-03122018-150548/.
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Este trabalho investigou a influência de diferentes solventes na liberação fotoinduzida do monóxido de carbono a partir do complexo [Ru3O(CH3COO)6(CO)(dmpz)2] (dmpz = 2,6-dimetilpirazina),e o comportamento solvatocrômico deste mesmo complexo e dos análogos [Ru3O(CH3COO)6(ampy)2(CO)] (ampy = 4-aminopiridina) e [Ru3O(CH3COO)6(py)2(CO)] (py = piridina). O complexo [Ru3O(CH3COO)6(CO)(dmpz)2] foi irradiado com laser em 377 nm em soluções de hexano, diclorometano, acetonitrila, metanol, etanol, 1-butanol, acetona, dimetilsulfóxido, água e tampão tris (pH=7,4).Estas irradiações foram acompanhadas por espectroscopia na região do UV-visível e o rendimento quântico da liberação fotoinduzida de monóxido de carbono foi calculado por meio de actinometria química de tris oxalato ferrato (III) de potássio. Com este estudo notou-se que o fotoproduto obtido depende do solvente utilizado, porém o rendimento quântico de liberação de CO não variou de forma significativa nos diferentes meios, indicando um mecanismo dissociativo no processo. Cálculos de TD-DFT para o complexo supracitado mostraram que,embora o complexo seja neutro, seu estado fundamental é mais polar do que seu estado excitado de transferência de carga, porém a diferença de polaridade entre os estados não foi considerada extensa. Análises do comportamento solvatocrômico dos complexos [Ru3O(CH3COO)6(ampy)2(CO)], [Ru3O(CH3COO)6(CO)(dmpz)2] e [Ru3O(CH3COO)6(CO)(py)2] também foram realizadas. Observou-se que cada composto apresentou um comportamento diferente, indicando a influência dos grupos substituintes nos ligantes terminais nas propriedades destes compostos. O complexo [Ru3O(CH3COO)6(ampy)2(CO)] apresentou deslocamento batocrômico da banda de transferência de carga do cluster para ligante (TCCL) com o aumento da polaridade dos solventes devido as características básicas do ligante terminal. Além de mostrar dependência com os solventes próticos utilizados, por conta das ligações de hidrogênio formadas entre o grupo amina do ligante e os solventes, bem como solvatação preferencial por metanol em misturas contendo este solvente prótico. O composto [Ru3O(CH3COO)6(CO)(dmpz)2], por sua vez, apresentou deslocamento hipsocrômico da banda TCCL com o aumento da polaridade dos solventes por conta das propriedades ácidas do ligante terminal e não apresentou dependência com solventes próticos, devido o impedimento estérico existente do nitrogênio não coordenado do ligante. Como esperado, o complexo [Ru3O(CH3COO)6(CO)(py)2] apresentou comportamento intermediário, pelo fato do ligante apresentar natureza intermediária dentro da série utilizada e não conter nenhum grupo substituinteThis work investigated the influence of different solvents on the photoinduced release of carbon monoxide from the complex [Ru3O(CH3COO)6(CO)(dmpz)2] (dmpz= 2,6 dimethylpyrazine), and the solvatocromic behavior of this same complex and the analogs [Ru3O(CH3COO)6(ampy)2(CO)] (ampy = 4-aminopyridine) and [Ru3O(CH3COO)6((CO)(py)2] (py = pyridine). The complex [Ru3O(CH3COO)6(CO)(dmpz)2] was irradiated by a laser at 377 nm in hexane, dichloromethane, acetonitrile, methanol, ethanol, 1-butanol, acetone, dimethylsulfoxide, water and tris buffer (pH = 7,4).These irradiations were accompanied by spectroscopy in the UV-Vis region and the quantum yield of the photoinduced release of carbon monoxide was calculated by chemical actinometry of potassium ferroxalate. By this study, it was observed that the photoproduct depends on the solvent used, but the quantum yield of CO release did not vary significantly in the different media used, indicating a dissociative mechanism in the process. TD-DFT calculations for the aforementioned complex have shown that although the complex is neutral, its ground state is more polar than its excited state of charge transfer, however the polarity difference between the states was not considered extensive. Analysis of the solvatocromic behavior of the complexes [Ru3O(CH3COO)6(ampy)2(CO)], [Ru3O(CH3COO)6(CO)(dmpz)2] and [Ru3O(CH3COO)6(CO)(py)2] were also performed. It was observed that each compound had a different behavior, indicating the influence of the substituent groups on the terminal ligands on the properties of these compounds. The [Ru3O(CH3COO)6(ampy)2(CO)] complex exhibited bathochromic shift of the charge transfer transition (CT) with increasing solvent polarity due to the basic characteristic of the terminal ligand. It also showed dependence with the protic solvents used, due to the hydrogen bonds formed between the amine group of the ligand and the solvents, as well as preferential salvation by methanol in mixtures containing this protic solvent.The compound [Ru3O(CH3COO)6(CO)(dmpz)2], on the other hand, presented a hypochromic shift of the charge transfer band with the increase of the polarity of the solvents due to the acidic properties of the terminal ligand and no dependence on protic solvents due to the steric hindrance of the uncoordinated nitrogen of the ligand. As expected, the [Ru3O(CH3COO)(CO)(py)2] complex exhibited intermediate behavior because the ligand has an intermediate nature within the series used an does not contain any substituent groups
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Jouaiti, Abdelaziz. "Activation electrochimique de petites molecules par des composes bi-metalliques et elaboration de films polymeres conducteurs." Université Louis Pasteur (Strasbourg) (1971-2008), 1989. http://www.theses.fr/1989STR13036.
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Reduction electrocatalytique de co::(2) dans le dmf en presence de ni(cyclam)**(2+) (bis cyclam)**(4+). Modification d'electrodes par polymerisation electrolytique de differents complexes de fe ii, co ii et ru ii avec le coordinat (p-pyrrolylmethylphenyl)-4' terpyridine-2,2:6',2". Ce nouveau type d'electrodes peut jouer le role de mediateur redox
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Zsoldos, Daniela. "Complexes mono et bis bipyridine carbonyle de ruthénium(II), précurseurs de polymères organométalliques : propriétés électrochimiques et applications à l'électrocatalyse de la réduction du CO2 en milieu aqueux." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10027.
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Ce memoire est consacre a l'etude de l'electrocatalytique de la reduction du co#2 par des complexes mono et bis bipyridine bis carbonyle de ru(ii), en phase homogene ou supportee (electrodes modifiees). Une partie de ce travail traite des proprietes electrochimiques des complexes trans-(cl)-cis-(co)-ru(l)(co)#2cl#2 (l = 2,2'-bipyridine substituee ou non ou 1,10-phenanthroline) et cis-(bpy)-cis-(co)-ru(bpy)#2(co)#2#2#+, precurseurs de polymeres du type ru(l)(co)#2#n, espece electrocatalytique clees. Le mecanisme d'electrogeneration de ces polymeres organometallique a pu etre determine, grace en particulier a l'etude des complexes stereoisomeres cis-(cl)-cis-(co)-ru(l)(co)#2xy#n#+(x = cl#- ; y = cl#- ou c(o)och#3#-). Ceux-ci ont un comportement electrochimique different des complexes equivalents trans-(cl)-cis-(co) et conduisent exclusivement a des dimeres. Tous ces complexes se sont averes etre d'excellents catalyseurs pour l'electroreduction du co#2 en milieu hydro-organique en phase homogene ou supportee. Par ailleurs, le probleme de l'instabilite a l'oxygene des electrodes modifiees par les films de ru(l)(co)#2#n a ete contourne grace a l'utilisation d'un autre type de cathodes moleculaires. Ces dernieres ont ete realisees par immobilisation, a la surface d'electrodes, des complexes precurseurs, dans des films de polypyrrole fonctionnalises. Une etude detaillee des differents parametres influencant l'orientation de la reaction de reduction du co#2 vers la production d'ions formiate (en particulier la substitution du ligand bipyridine) dans un electrolyte purement aqueux, a permis d'etablir les conditions optimales pour l'obtention de rendements electriques quasi quantitatifs.
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Bitsi, Gustave Adolphe. "Catalyse et cocatalyse de quelques reactions organiques par les composes de ruthenium." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13037.
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Rahmouni, Noureddine. "Synthese et reactivite de complexes dinucleaires des metaux de transition." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13080.
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Synthese de complexes dinucleaires de cu(ii)-dppm, presentant des proprietes magnetiques interessantes et de cu(i)-dppm dont on etudie la structure. Etude particuliere de rh::(2)(dppm)(co)**(2+) et rh(dppm)::(2)(co)::(2)(mu -co)**(2+). Grande reactivite de ce dernier, notamment avec un alcyne terminal phcch dans lequel une activation c-h a lieu pour conduire a un complexe mu -eta -acetylene
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FRANCHI, DANIELE. "Optimization of components for Dye-Sensitized Solar Cells: a combined approach for performance improvement." Doctoral thesis, 2017. http://hdl.handle.net/2158/1079132.
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Photovoltaic devices are capable of converting light into an orderly flow of charges also known as Electricity. Dye-Sensitized Solar Cells (DSSCs) are newgeneration photovoltaic devices in which the component capable of absorbing light and creating a separation of electric charges are dye molecules adsorbed on a semitransparent thin layer of a semiconductor.
Despite their simple architecture, DSSCs are devices characterized by a very complex entanglement of physical variables, each one interacting with the others to determine macroscopic features of the device. For example: the energy levels of the photoactive compound set limits on the portion of solar light that will be absorbed; the orbital overlap between the semiconductor substrate and the dye rule on the electron injection; the electron density on the solid surface and the ions concentration in the liquid charge carrier shape the outcome voltage. The all of this parameters, and many more, needs to be tuned each other to convert the solar energy with the best efficiency.
In this piece of writing, I am analyzing tree of the main parts of DSSCs: the semiconductor solid surface, the photoactive dye material, and the electrolyte charge transporter. Not only will efficiency issue be addressed, but also longevity of the devices, generally hampered by dye degradation or electrolyte evaporation; esthetical needs such as transparency and color; and deep understanding of nanocomposites or ionic liquids application response will be addressed.
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Sun, Bian-Jian, and 孫秉建. "Reaction dynamics of the systems of carbon chain species, and pyridine formation." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/39233498896002503683.
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博士國立東華大學
化學系
98
The interstellar reaction of ground-state carbon atom with the simplest polyyne, diacetylene (HCCCCH), is investigated theoretically to explore probable routes to form hydrogen-deficient carbon clusters at ultra-low temperature in cold molecular clouds. The isomerization and dissociation channels for each of the three collision complexes are characterized by utilizing the unrestricted B3LYP/6-311G(d,p) level of theory and the CCSD(T)/cc-pVTZ calculations. With facilitation of RRKM and variational RRKM rate constants at collision energies of 0-10 kcal/mol, the most probable paths, thus reaction mechanism, are determined. Subsequently the corresponding rate equations are solved that the evolutions of concentrations of collision complexes, intermediates, and products versus time are obtained. As a result, the final products and yields are identified. This study predicts that three collision complexes, c1, c2, and c3, would produce a single final product, 2,4-pentadiynylidyne, HCCCCC(X2Π), C5H (p1) + H, via the most stable intermediate, carbon chain HC5H (i4). Our investigation indicates the title reaction is efficient to form astronomically observed 2,4-pentadiynylidyne in cold molecular clouds, where a typical translational temperature is 10 K, via a single, bimolecular gas phase reaction.
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Hong, Xiu-Xuan, and 洪秀萱. "Thermal and Photochemical Reactions of Pyridine-3-Carbonyl Azide on a Cu(100) Surface." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9f2y77.
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碩士國立中山大學
化學系研究所
107
The thermochemical and photochemical reactions of pyridine-3-carbonyl azide (Py-C(=O)N3) on Cu(100) have been studied in ultrahigh vacuum by reflection-absorption infrared spectroscopy and temperature-programmed desorption. Unexpectedly, the classical thermal-Curtius rearrangement of acyl azide was not observed in this work. Instead, after rupturing the N-N2 bond upon heating, an oxazirene-like structure, the resonance form of acylnitrene, led to coadsorbed pyridine-3-cyanate (Py-OCN) and pyridine-3-nitrile N-oxide (Py-CNO) intermediates which are substantiated by DFT calculations. The endproduct was 3-pyridinecarbonitrile (Py-CN) confirmed by TPD and IR spectrum. However, only by UV photoirradiation can the Curtius rearrangement product, pyridine-3-isocyanate (Py-NCO), be generated. The photolysis reaction was incomplete; therefore, the remaining unreacted azido species proceeded via the thermochemical pathway to produce Py-CN. Furthermore, RAIRS data showed no evidence for the presence of an acylnitrene (Py-C(=O)N) intermediate, suggesting that the surface photo-Curtius reaction is concerted.
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"(Pyrazolylpyridine)- iron, cobalt and nickel complexes as carbon-carbon bond formation catalysts." Thesis, 2011. http://hdl.handle.net/10210/3642.
Full textAbstract:
M.Sc.2-(Pyrazol-1-ylmethyl)pyridine ligands were synthesised by phase transfer alkylation of 2-picolyl hydrochloride with the appropriate pyrazole. These ligands were subsequently reacted with NiCl2, NiBr2, FeCl2 or CoCl2 to form the respective complexes. The substituents on the pyrazole included phenyl and tert-butyl groups as well as electron withdrawing CF3 groups. The substituents played an important role in the steric and electrophilic nature of the metals. A second ligand design is 2,6-bis(pyrazol-1-ylmethyl)pyridine and were prepared by phase transfer alkylation of 2,6-bis(chloromethyl)pyridine with two mole equivalents of the appropriate pyrazole. These ligands were reacted with NiCl2, NiBr2, FeCl2 or CoCl2 to form the respective complexes. A third ligand design is 2-(chloromethyl)- or 2-(bromomethyl)-6-(pyrazol-1-ylmethyl)pyridine and were prepared by the selective alkylation of 2,6-bis(chloromethyl)pyridine with one mole equivalent of the appropriate pyrazole. These ligands were also reacted with NiCl2, NiBr2, FeCl2 or CoCl2 to form the respective complexes. Characterisation of all compounds was done by a range of spectroscopic techniques as well as X-ray crystallography and elemental analysis. The data showed good fit to the proposed structures and in a few cases were confirmed by X-Ray crystallography. All complexes were tested as catalysts for ethylene and higher olefin oligomerisation and showed good activity. The production of alkenes were confirmed in toluene and hexane, however, due to the use of EtAlCl2 and toluene the oligomers were alkylated to form the Friedel-Crafts alkylation products. Similar alkylation was observed for the higher olefin reactions. In comparison, the same reactions in hexane resulted in only C4, C6 and C8 oligomers. When higher olefin reactions were also conducted in hexane, polymeric solids were observed.
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Zhuang, Xin-Yi, and 莊新毅. "Synthesis of Benzo[4,5]imidazo[1,2-a]pyridine and its derivatives by intermolecular carbon-nitrogen bond coupling reaction between aniline and pyridine induced by different aromatic substituted hypervalent iodine reagents." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/ncwgwy.
Full textAbstract:
碩士國立中山大學
化學系研究所
107
In this thesis, we have successfully found two types of highpervalent iodine reagents with different substituent groups: (4-methoxyphenyl)- λ3-iodanediyl diacetate and (4-methoxyphenyl)- λ3-iodanediyl diacetate, increasing the yield of the production of benzo[4,5]imidazo[1,2-a]pyridines with aniline derivatives and pyridine derivatives as starting materials. In this thesis, we have successfully found two types of highpervalent iodine reagents with different substituent groups: (4-methoxyphenyl)- λ3-iodanediyl diacetate and (4-methoxyphenyl)- λ3-iodanediyl diacetate, increasing the yield of the production of benzo[4,5]imidazo[1,2-a]pyridines with aniline derivatives and pyridine derivatives as starting materials. Compounds with benzo[4,5]imidazo[1,2-a]pyridine skeletons are compound is obtained, and the yields are between 50% and 80%. Furthermore, the structures of two products and highpervalent iodine reagents are provided. The structures are confirmed by the x-ray single crystal diffraction technique, and are also promising in the pharmaceutical industry. Therefore, we also hope we are able to rapidly produce the compounds possessing this structure with the facile synthetic strategy herein.
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He, Haoze. "Synthesis, Characterization and Application of Poly (Styrene-4- Vinyl Pyridine) Membranes Assembled With Single-Wall Carbon Nanotubes." Thesis, 2011. http://hdl.handle.net/10754/209398.
Full textAbstract:
Poly(styrene-4-vinylpyridine) (PS-P4VP) isoporous membranes were prepared
and their properties were evaluated in this research. The solution was prepared by
dissolving PS-P4VP polymer with necessary additives into a 1:1:1 1,4-dioxane –
N,N-dimethyl formamide – tetrahydrofuran (DOX-DMF-THF, DDT) solvent. Then
0.5-1.0 mL of the primary solution was cast onto the non-woven substrate
membrane on a glass slide, evaporated for 15-20 sec and immersed into de-ionized
water for more than 30 min for the solidification of isoporous structure and for the
formation of the primary films, which could be post-processed in different ways for
different tests. The membrane surface presents a well-ordered, hexagonal
self-assembly structure, which is fit for aqueous and gaseous filtration. The pore
size of the isoporous surface is 30~40 nm. The pore size is also sensitive to [H+] in
the solution and a typical pair of S-shape pH-correlation curves with significant
hysteresis was found. Four techniques were tried to improve the properties of the
membranes in this research: 1) 1,4-diiodobutane was introduced to chemically
change the structure as a cross-linking agent. 2) single-wall carbon nanotube
(SWCNT) was linked to the membranes in order to strengthen the stability and rigidity and to reduce the hysteresis. 3) Homo-poly(4-vinylpyridine) (homo-P4VP)
was added and inserted into the PS-P4VP micelles to affect the pore size and surface
structure. 4) Copper acetate (Cu(Ac)2) was used as substitute of dioxane to prepare
the Cu(Ac)2-DMF-THF (CDT) mixed solvent, for a better SWCNT dispersion. All the
possible improvements were judged by the atomic force microscopy (AFM) images,
water and gas flux tests and pH-correlation curves. The introduction of SWCNT was
the most important innovation in this research and is promising in future
applications.
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Lin, Pi-shan, and 林碧珊. "Palladium(II)-Catalyzed Synthesis of 2-(Biphenyl-2-yloxy)pyridines and N-Pyridylcarbazoles via Carbon-Hydrogen Bond Activation." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/60529171183590090694.
Full textAbstract:
碩士國立中山大學
化學系研究所
99
This thesis is composed of two parts. The palladium-catalysted synthesis of 2-arylphenols and carbazoles via carbon-hydrogen (C-H) bond activation is described. Treatment of 2-phenoxypyridines with two and a half equivalents of potassium aryltrifluoroborate and 10 mol % of Pd(OAc)2 in the presence of two equivalents of Ag2CO3, one equivalent of p-benzoquinone (BQ), and four equivalents of DMSO with (or without) H2O at 130-140 oC for 48 h in dried CH2Cl2 gave the ortho-arylated 2-phenoxypyridines in modest to excellent yields. The investigation of kinetic isotope effect (kH/kD) is determined to be 5.25, which indicates that C-H bond cleavage occurs in the rate-determining step. 2-(Biphenyl-2-yloxy)pyridines was treated with methyl trifluoromethanesulfonate and subsequently sodium methoxide to give the 2-arylphenols to demonstrate the pyridine is a removable directing group. On the other hand, a novel one-pot synthesis for N-pyridylcarbazoles by the reaction of N-phenylpyridin-2-amines with potassium aryltrifluoroborates using Pd(OAc)2 as the catalyst is presented. For instance, reaction of N-phenylpyridin-2-amines with four equivalents of potassium aryltrifluoroborate under the optimal reaction condition gave N-pyridylcarbazoles in 67% yield along with N-(biphenyl-2-yl)pyridin-2-amine in 13% yield. The investigation of kinetic isotope effect (kH/kD) for first C-H bond activation/C-C bond formation step is determined to be 2.14, and that of the second C-H bond activation/C-N bond formation steps is 1.18. On the basis of KIE analysis, it might indicate that first C-H activation undergo direct C-H bond cleacage, and second step should be via electrophilic aromatic substitution.
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林榮安. "The study of synthesis and formulation of ([[[4-amino carbonyl)pyridino]methoxy]-methyl]-2-[[hydroxy imino]methyl]-pyridinium dichloride,HI-6." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/33948208987695209959.
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Fang, Yung-Cheng, and 方勇程. "(a)Structures and Calculations of New Fluoro-ponytailed Pyridines and Their Trans Palladium Halide Complexes (b)Calculations of Fluoro-containing Compounds and Research of Carbon-deuterium Stretching." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/bdwzq3.
Full textAbstract:
碩士國立臺北科技大學
有機高分子研究所
105
B. Calculations of Fluoro-containing Compounds and Research of Carbon-deuterium Stretching. Since the structure obtained by X-ray diffraction has a bigger deviation on the bond length, the optimized structure of the compound is calculated by the method of density functional theory (DFT) using the theoretical calculation method. With the vibration spectrum, and with the IR spectrum of the experimental data, assigned each signal represents the vibration mode. We also tried to replace some of the hydrogen atom the fluorine-containing pyridine with a deuterium atom to help us assign the vibrational mode by considering the displacement of the signals.