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Ahern, J. M. "Radical hydroacylation of C-C and N-N double bonds in air." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1309819/.
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The formation of C-C and C-N bonds in modern organic synthesis is a key target for methodological advancement. Current methods of C-C and C-N bond formation often involve the use of expensive catalysts, or sub-stoichiometric reagents, which can lead to the generation of undesirable waste products. This thesis describes a novel and environmentally benign set of reaction conditions for the formation of C-C and C-N bonds by hydroacylation and this is promoted by mixing two reagents, an aldehyde and an electron-deficient double bond, under freely available atmospheric oxygen at room temperature Chapter 1 will provide an introduction to the thesis and mainly discusses methods for C-C bond formation, in particular, radical chemistry and hydroacylation. Chapter 2 describes the hydroacylation of vinyl sulfonates and vinyl sulfones (C-C double bonds) with aliphatic and aromatic aldehydes with a discussion and evidence for the mechanism of the transformation. Chapter 3 details the synthesis of precursors for intramolecular cyclisations and studies into aerobic intramolecular cyclisations. Chapter 4 describes the hydroacylation of vinyl phosphonates (C-C double bonds) and diazocarboxylates (N-N double bonds) with aliphatic and aromatic aldehydes bearing functional groups. In addition, the hydroacylation of diazocarboxylates with chiral aldehydes will be discussed. In conclusion, a new, facile and clean set of reaction conditions for the formation of C-C and C-N bonds has been developed via aerobic C-H activation of aldehydes providing access to unsymmetrical ketones.
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Qian, Xin. "Cobalt-Catalyzed C-C and C-N Coupling reactions." Phd thesis, Ecole Polytechnique X, 2013. http://pastel.archives-ouvertes.fr/pastel-00943479.
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Ce travail de these a permis le déveloippement de nouvelles reactions de couplage catalysées par des sels de cobalt(II) Le premier chapitre décrit l'allylation cobalta catalysée d'halogénures d'alkyles. La méthode est facile à mettre en œuvre, efficace avec une grande variété d'halogénures d'alkyes et des acétates ou carbonates d'allyle substitués. Les rendements vont de bons à excellents et la tolérance fonctionnelle élevée. Dans le cas d'acétates d'allyle substitués le produit linéaire est obtenu majoritairement ou exclusivement. Quelques expériences ont permis de mettre en lumière la formation d'espèce radicalaire lors du cycle catalytique. Les premiers essais pour étendre cette méthodologie aux couplages allyle-allyle et alkyle-alkyle sont également décrits. Le deuxième chapitre porte sur l'amination catalysée au cobalt d'organozinciques fonctionnalisés en utilisant des N-chloroamines. La procédure est simple et générale et demande des conditions plus douces que celles précédemment décrite, tout en tolérant un très large éventail de substrats, avec une bonne tolérance à de nombreux groupes fonctionnels. Les premiers essais pour étendre la méthodologie à la réaction entre un organozincique et une source électrophile de soufre en vue de former des liaisons C-S sont également exposés. Enfin le dernier chapitre décrit la réaction d'organozinciques engendrés par catalyse au cobalt avec une source " verte " de cyanure électrophile, N-cyano-N-phenyl-p-methyl-benzenesulfonamide (NCTS), pour conduire avec de bons rendements aux arylnitriles correspondants. Des sources analogues de CN+ ont également été testées.
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Simayi, Rena. "Synthesis and reaction chemistry of various N,N,C- and O,N,C- palladium pincer complexes." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/39392.
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In this thesis, the synthesis, characterisation and complexation chemistry of a series of related NNC and ONC pyridine based pincer ligands, together with some reaction chemistry of the metal complexes is described. The pro-ligands and the metal complexes have been characterised by a combination of multinuclear NMR spectroscopic techniques, IR spectroscopy, mass spectrometry and, for selected examples, by single crystal X-ray crystallography; remarkable spectroscopic and structural data are discussed. In Chapter 2, the synthesis and characterization of thirteen NNC and ONC pyridine based pincer ligands is described, including nine novel pincer ligands and four pyridine based pincers which have been previously reported. In Chapter 3, the palladium/platinum chemistry of NNCaryl and ONCaryl pyridine based pincer ligands is explored. Variation on the donor atoms has allowed an investigation of donor property influences on C-H activation, by giving peri-activated palladium pincer complexes for the ketimine-, aldimine-, amine- and biyridine-armed ligands and generating ortho-activated ONC palladium pincer complexes in the case of the alcohol-armed pro-ligand. Use of different palladium salts also led to different regioselective C-H activations. With the ketimine-armed naphthyl ligand (HL1ket-nap) as the example, the interconversion chemistry between the ortho- and peri-C-H activated products is also explored. In Chapter 4, sp3 C-H activation of the Et-armed ligand HL4Et with both palladium acetate and palladium chlorides has been unsuccessful, giving the N,N-coordinated bidentate species. The reaction of palladium acetate with the iPr-armed pro-ligand HL4iPr has resulted in minor amounts of C-H activated vinyl species with the major product being the non-activated palladium diacetate complex. Noticeably, upon reaction with Na2PdCl4, a mixture of the non-activated bis-chloride palladium complex and the sp3 C-H activated NNC-tridentate palladium species has been obtained, in a ratio of 1:1.5. Moreover, the sp3 C-H activation and the isolation of a rare sp3 C-H activated palladium complex have been achieved by reacting the tBu-armed pro-ligand HL4tBu with palladium acetate. The reaction of this ligand with Na2PdCl4 also resulted in the successful C-H activation of the tBu-arm to give a palladium pincer complex with a yield of 95%. Other than the NMR and FABMS analyses, the solid state X-ray structure of the latter complex confirmed the formation of the material as a rare sp3 C-H activated palladium complex. The stoichiometric reactivity of the (NNC/ONC)PdCl species towards AgBF4/AgPF6, and the subsequent ligand exchange reactions are disclosed in Chapter 5, together with the application of twelve palladium complexes as a series of promising catalysts in the allylic arylation of various allylic acetates with sodium tetraphenylborate.
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Huang, Xiaohua 1973. "Palladium-catalyzed C-C, C-N and C-O bond formation." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29639.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2003.Vita.
Includes bibliographical references.
New methods for Pd-catalyzed cross-coupling reactions of aryl halides or arenesulfonates are described. Key to the success of these transformations is the proper choice of ligand and reaction conditions. Palladium catalysts supported by bulky, monodentate phosphine ligands with a biaryl backbone or the bidentate ligand, Xantphos, effectively promote the formation of ca-aryl carbonyl compounds. Base-sensitive functional groups are better tolerated when a weak base, such as K3PO4, is used. One of the most difficult transformations in Pd catalysis, the intermolecular C-O bond formation between primary alcohols and electron-neutral or even electron-rich aryl halides, was effectively promoted by the use of a new generation of ligands, 3-methyl-2-di-t-butylphosphinobiaryl. The one-step synthesis of ligands from cheap starting materials, as well as the mild reaction conditions employed for the coupling reactions, enables the practical use of Pd catalysis to access aryl alkyl ethers for the first time. Continuing study of Pd-catalyzed C-N bond-forming processes using biaryl monophosphine ligands led to the discovery of a structural derivative of these ligands, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl. This ligand, in combination with a Pd source, produces a catalyst system with both a greater degree of activity and of stability than those that use our previous ligands. Substrates that were not amenable to Pd catalysis previously are reexamined using this new catalyst system, and excellent results are obtained.
by Xiaohua Huang.
Ph.D.
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Cómbita, Merchán Diego Fernando. "Formación de enlaces C-C, C-N y N-N con catalizadores de óxido de cerio y de oro/óxido de cerio." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/62780.
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[EN] Heterogeneous catalysis is one of the most important tools in the advancement of green chemistry, understood it as one that efficiently uses (preferably renewable) raw materials, eliminate waste and avoids the use of toxic and/or dangerous reagents and solvents in chemicals production and application.
In this thesis we have investigated the reaction mechanisms and the nature of the active centers in C-C, C-N and N-N bond forming reactions over cerium oxide and over gold nanoparticles supported on cerium oxide heterogeneous catalysts.
As C-C bond formation reaction, we had been studied Sonogashira reaction catalyzed by a heterogeneous Au/CeO2 catalyst, wherein the CeO2 nanoparticle is about 5 nm in diameter.
The second part of the thesis comprises the study of C-N bonds formation during carbamoylation reaction between diaminotoluene and dimethyl carbonate, catalyzed by cerium oxide, studying the effect over the reaction of the crystal planes available for reactants adsorption.
In a third part, the N-N bond formation in the reductive coupling reaction of nitrocompounds to obtain azocompounds was studied, using Au/CeO2 as heterogeneous catalyst. Also in this section we report, by first time, an active and selective heterogeneous catalyst for the Mills reaction between nitroso compounds and anilines to obtain symmetric and asymmetric azocompounds.[ES] La catálisis heterogénea es una de las más importantes herramientas para el desarrollo de la Química Sostenible, entendida como aquella que utiliza eficientemente las materias primas (preferiblemente renovables), elimina los desechos y evita el uso de reactivos y solventes tóxicos y/o peligrosos en la manufactura y aplicación de los productos químicos. En esta tesis doctoral se han investigado los mecanismos de reacción y la naturaleza de los centros activos, en reacciones de formación de enlaces C-C, C-N, y N-N sobre catalizadores heterogéneos de óxido de cerio y de nanopartículas de oro soportadas en óxido de cerio. Como reacción de formación de enlaces C-C se ha estudiado la reacción de Sonogashira catalizada con un catalizador heterogéneo de Au/CeO2, en donde el CeO2 está en forma de nanopartículas de cerca de 5nm de diámetro. En la segunda parte de la tesis se profundiza en el estudio de la formación de enlaces C-N durante la reacción de carbamoilación del diaminotolueno con dimetilcarbonato catalizada por el óxido de cerio, estudiando el efecto que tiene sobre la reacción la naturaleza de los planos cristalinos disponibles para la adsorción de los reactivos. En una tercera parte se estudia la formación de enlaces N-N en la reacción de acoplamiento reductivo de nitrocompuestos para obtener azocompuestos en presencia de un catalizador heterogéneo de Au/CeO2. Es este mismo apartado se reporta por primera vez un catalizador heterogéneo de alta actividad y selectividad para la Reacción de Mills entre un nitrosocompuesto y una anilina para obtener azocompuestos simétricos y asimétricos.
[CAT] La catàlisi heterogènia és una de les ferramentes més importants per al desenvolupament de la Química Sostenible, entesa com aquella que utilitza eficientment les matèries pimes (preferiblement renovables), elimina els rebutjos i evita l'ús de reactius i dissolvents tòxics i/o perillosos en la manufactura i aplicació dels productes químics. En esta tesi doctoral s'han investigat els mecanismes de reacció i la natura dels centres actius, en reaccions de formació d'enllaços C-C, C-N i N-N sobre catalitzadors heterogenis d'òxid de ceri i nanopartícules d'or suportades en òxid de ceri. Com reacció de formació d'enllaços C-C s'ha estudiat la reacció de Sonogashira catalitzada amb un catalitzador heterogeni d'Au/CeO2, on el CeO2 està en forma de nanopartícules amb un diàmetre proper als 5nm. En la segona part de la tesi s'aprofundeix en l'estudi de la formació d'enllaços C-N durant la reacció de carbamilació del diaminotoluè amb dimetilcarbonat catalitzada per l'òxid de ceri, estudiant l'efecte que té sobre la reacció la natura dels plans cristal·lins disponibles per a l'adsorció dels reactius. En una tercera part s'estudia la formació d'enllaços N-N en la reacció d'acoblament reductiu de nitrocompostos per a obtenir azocompostos en presència d'un catalitzador heterogeni d'Au/CeO2. En aquest mateix apartat es reporta per primera vegada un catalitzador heterogeni d'alta activitat i selectivitat per a la Reacció de Mills entre un nitrocompost i una anilina per a obtenir azocompostos simètrics i asimètrics.
Cómbita Merchán, DF. (2016). Formación de enlaces C-C, C-N y N-N con catalizadores de óxido de cerio y de oro/óxido de cerio [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62780
TESIS
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Roberts, Deborah Elizabeth. "Palladium N-neterocyclic carbene complexes as catalysts for C-N, C-Si and C-S bond formations." Thesis, University of Sussex, 2013. http://sro.sussex.ac.uk/id/eprint/45342/.
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This work is foremost a study of various palladium-bearing N-heterocyclic carbenes complexes and their catalytic potential to form C-N bonds. Both alkyl amination and aryl amination are considered. Further elucidation on the mechanism of such catalytic activity is investigated. The viability of alkyl amination using palladium complexes bearing the ligands, ITMe, 1,2,3,4- tetramethylimidazol-2-ylidene, and ICy, 1,3- bis-cyclohexylimidazol-2-ylidene, as catalysts, is investigated. This includes the synthesis of [Pd(ITMe)(neopentyl)Cl]2,[Pd(ITMe)2(neopentyl)Cl], [Pd(ITMe)(neopentyl)(tbutylamine)Cl], [Pd(ITMe)(neopentyl)(hexylamine)Cl], with successful elimination of the alkyl-amination reaction product in low yield from the latter complex. [Pd(ICy)(neopentyl)Cl]2, [Pd(ICy)2(neopentyl)Cl] are also isolated. Unsuccessful attempts were made to vary the electronic properties of the complexes by replacing the amine with a hydrazine. Work was also done on indirect alkylation using tBuLi which led to a new method for synthesis of [Pd(ItBu)2] and novel complex, [Pd(ItBu)Cl3. ItBuH] (ItBu = 1,3- bis-tertbutylimidazol-2-ylidene). Aryl amination catalysed by complexes of palladium bearing the ligand, ITMe, is considered. This includes an improved synthesis of [Pd(ITMe)2] and synthesis of [Pd(ITMe)2(anisole)Cl]. Unsuccessful attempts at the elucidation of the mechanism of [Pd(ITMe)2(anisole)] formation led to the unexpected formation of [Pd(ITMe)2(SiMe3)(Si(SiMe3)3)] and [Pd(ITMe)2(SiMe3)2]. Aryl amination with using [Pd(ITMe)2(SiMe3)2] led to two aryl amination products, 4-ortho-methoxyphenyl morpholine as well as the expected para isomer. The use of complexes [Pd(ItBu)2] and [Pd(SIPr)2] (SIPr = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) in C-S bond formation was explored. Addition of mesityl magnesium bromide to Pd(1,5-COD)Cl2 led to addition of mesityl substrate across 1,5-COD double bond and the addition of ITMe formed the Heck cycle intermediate [Pd(8-mesityl-1,4,5-η3 – C8H12)X2] (X=Cl, Br). Addition of 4-tolyl magnesium chloride resulting in the formation of Pd(ItBu)2(tolyl)Cl via an indirect route.
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Neal, Richard J. "The loosely-bound proton in ¹³N and the transfer reaction ¹¹B(¹³N,¹²C)¹²C." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/1783.
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The radioactive nucleus ¹³N (t½ = 10 min, Jπ = ½) contains one loosely bound proton (Sp = 1.94 MeV) which can be considered to be bound to a core of ¹²C. Taking advantage of the recent availability of beams of radioactive nuclei at Louvain-la-Neuve, Belgium, a beam of ¹³N has been used to investigate the transfer reaction ¹¹B(¹³N,¹²C)¹²C. Particle-γ coincidence data was taken, using the LEDA silicon strip array and BaF₂ modules, gating on the 15.11 MeV γ-decay from the T = 1 state in ¹²C*. Two final states, corresponding to ¹²Cgs + ¹²C*(15.11 MeV) and ¹²C*(4.44 MeV)+ ¹²C*(15.11 MeV) have been observed and angular distributions have been measured for both transitions at each of two beam energies, 29.5 MeV and 45 MeV. The results are discussed with special reference to the loosely bound nature of the valence proton in ¹³N; the transfer reaction has been modelled using a DWBA code, with the ¹³N ground state constructed as a mixture of states: a p½ proton bound to ¹²Cgs , or a p3/2 proton bound to ¹²C*₂₊ (4.44 MeV). Fits to the experimental data have been obtained using a very shallow set of optical potentials, which are found to be energy dependent. The agreement with experiment is good, with the exception of the ¹²C*(4.44)+¹²C*(15.11) transition at the lower beam energy, which is significantly underestimated by the calculations, suggesting a contribution from a different reaction mechanism.
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Ounaïes, Myriam. "Ensembles inévitables pour les applications holomorphes de C [exposant] n dans C [exposant] n." Toulouse 3, 1995. http://www.theses.fr/1996TOU30140.
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En une veriable complexe, l'image d'une fonction meromorphe evite au plus deux points de la sphere de rieman: c'est le theoreme de picard. De plus, grace a la theorie de nevanlinna, nous savons que chaque valeur est prise dans le disque de rayon r avec la meme frequence asymptotique sauf pour un ensemble denombrable de valeurs. En plusieurs variables, on observe un phenomene different. Il existe en effet des applications holomorphes, injectives, de c#n dans c#n dont l'image n'est pas dense dans c#n: ce sont les applications de fatou-bieberbach. Rosay et rudin ont montre qu'il existe pourtant des ensembles discrets qui doivent rencontrer l'image de toute application holomorphe non degeneree ; nous les appellerons ensembles inevitables. L. Gruman a construit explicitement une famille de tels ensembles e(a) parametres par a dans c*#n. Nous montrons que chaque ensemble e(a) est rencontre dans la boule de rayon r avec la meme frequence asymptotique pour tout a dans c*#n. Ceci constitue une sorte d'analogue a la theorie de nevanlinna en plusieurs variables
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Mudarra, Alonso Ángel Luis. "Coinage complexes in C-C and C-N bond-forming reactions." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/670357.
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Els complexos organometàl·lics de coure, plata i or juguen un paper fonamental com espècies reactives
en diverses transformacions químiques. Aquesta tesi aporta coneixement sobre el comportament
d’aquests complexos en la formació d’enllaços C-C i/o C-N. En concret, estudiem: i) el mecanisme de
reacció a través del qual els complexos de coure co-catalitzen un acoblament oxidant en el context de
sistemes bimetàl·lics de rodi i coure; ii) el potencial de nucleòfils de plata com a agents transmetal·lants
en reaccions de trifluorometilació catalitzades per pal·ladi; iii) el mecanisme de reacció de sistemes
bimetàl·lics de Pd/Ag emprant un sistema model; i iv) el comportament de complexos bis(trifluorometil)
cuprat, argentat i aurat com a nucleòfils. En aquesta tesi, on s´han combinat estudis experimentals i
computacionals, s’ha adquirit nou coneixement sobre els processos estudiats, i s’ha contribuït al camp de
la recerca química basada en el coneixement.Los complejos organometálicos de cobre, plata y oro juegan un papel fundamental como especies reactivas en diversas transformaciones químicas. Esta tesis aporta conocimiento sobre el comportamiento de estos complejos en la formación de enlaces C-C y/o C-N. En concreto, estudiamos: i) el mecanismo de reacción por el cual complejos de cobre co-catalizan un acoplamiento oxidante en el contexto de sistemas bimetálicos de rodio y cobre; ii) el potencial de nucleófilos de plata como agentes transmetalantes en reacciones de trifluorometilación catalizadas por paladio; iii) el mecanismo de reacción de sistemas bimetálicos de Pd/Ag usando un sistema modelo; y iv) el comportamiento de complejos bis(trifluorometil) cuprato, argentato y aurato como nucleófilos. En esta tesis, donde se han combinado estudios experimentales y computacionales, se ha adquirido nuevo conocimiento sobre los procesos estudiados, y se ha contribuido al campo de la investigación química basada en el conocimiento.
Organometallic coinage metal complexes are be key reactive species for promoting a wide variety of chemical transformations. This thesis improves the understanding the behavior of these complexes in relevant C-C and/or C-N bond-forming reactions. Specifically, we have explored: i) the mechanistic intricacies of copper species as co-catalyst in the context of rhodium/copper-catalyzed oxidative coupling reactions; ii) the capability of silver nucleophiles as transmetalating agents in palladium-catalyzed trifluoromethylation reactions; iii) the reaction mechanism of Pd/Ag bimetallic reactions using a model system as probe; and, iv) the study of bis(trifluoromethyl) coinage metallates as nucleophiles. The fundamental insights gathered in this Thesis, encompassing both experimental and computational approaches, improve our understanding of the processes under study and make a contribution to the general field of knowledge-driven research in Chemistry.
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Kanuru, Vijaykumar. "Understanding surface mediated C-C and C-N bond forming reactions." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608956.
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Raghuvanshi, Keshav. "Ruthenium(II)-Catalyzed C-N, C-O and C-C Formations by C-H Activation." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://hdl.handle.net/11858/00-1735-0000-002B-7D4C-2.
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Laren, Martijn Wouter van. "Palladium-catalyzed C-H and C-N bond formation." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2004. http://dare.uva.nl/document/75422.
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Bollwein, Tobias. "Metallierung, oxidative C-C-Kupplung und C-N-Aktivierung mit Zinkorganyl-Verbindungen." Diss., [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963033077.
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Kulchat, Sirinan. "Dynamic covalent chemistry of C=N, C=C and quaternary ammonium constituents." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF018/document.
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Cette thèse décrit la Chimie Covalente Dynamique (CCD) des échanges imine/imine, Knoevenagel/imine et Knoevenagel/Knoevenagel. La L-proline est un excellent organocatalyseur pour la formation de Bibliothèques Covalentes Dynamiques (BCDs). Cependant, l’interconversion entre des dérivées Knoevenagel de l’acide diméthylbarbiturique et des imines se déroule rapidement sans catalyseur. Une nouvelle classe de CCD basée sur des échanges par substitutions nucléophiles (SN2/SN2’) entre des sels d’ammonium quaternaires et des amines tertiaires est développée, impliquant la catalyse par l’iodure. Les réactions d’échange entre des sels de pyridinium et un dérivé de pyridine génèrent des liquides ioniques dynamiques. Enfin, la sélection cinétique et thermodynamique de la formation d’imines dans la CCD est réalisée en solution aqueuse e ten solvant organiqueThis thesis describes the dynamic covalent chemistry (DCC) of imine/imine, Knoevenagel/imine, and Knoevenagel/Knoevenagel exchange. L-proline is shown to be an excellent organocatalyst to accelerate the formation of dynamic covalent libraries (DCLs). The interconversion between Knoevenagel derivatives of dimethylbarbituric acid and imines is found to occur rapidly in the absence of catalyst. A new class of DCC based on nucleophilic substitution (SN2/SN2’) component exchange between quaternary ammonium salts and tertiary amines is developed, by the use of iodide as a catalyst. The exchange reactions between pyridinium salts and a pyridine derivative generate dynamic ionic liquids. Finally, kinetic and thermodynamic selection of imine formation in a DCC is perfomed in aqueous solution and organic solvent
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Desmarchelier, Alaric. "Cascades réactionnelles organocatalysées : création stéréosélective de liaisons C-N et C-C." Versailles-St Quentin en Yvelines, 2012. http://www.theses.fr/2012VERS0031.
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Les travaux exposés dans ce manuscrit ont pour objectif l’étude de cascades réactionnelles organocatalysées permettant de former stéréosélectivement des liaisons C-N, et C-C. Plusieurs approches « one-pot » séquentielles ont été développées à partir de substrats simples, conduisant à des produits hautement fonctionnalisés. Le premier chapitre se focalise sur la formation énantiosélective d’aziridines portant un centre quaternaire, à partir d’énals α-substitués. La difonctionnalisation en position α d’aldéhydes a ensuite été étudiée par double activation énamine. Le deuxième chapitre traite ainsi d’une séquence réaction de Mannich/amination électrophile sur l’acétaldéhyde, pour accéder à des diamines vicinales. Le troisième chapitre décrit la cascade réaction de Michael/amination électrophile, conduisant à la formation d’hydrazinoaldéhydes possédant un centre quaternaire. Enfin, le dernier chapitre se concentre sur l’amination électrophile d’aldéhydes α,α-disubstitués, et son application en cascade organocatalysée pour former des hétérocycles azotés, les 3-pyrrolines, portant un centre quaternaireThe work presented in this manuscript aims at the study of organocascade reactions enabling the stereoselective formation of C-N and C-C bonds. Several sequential one-pot approaches yielding highly functionalized products from simple substrates have been developed. The first chapter describes the enantioselective synthesis of aziridines from α-substituted enals. α-difunctionalization of aldehydes has then been studied via double-enamine activation. The second chapter presents a one-pot Mannich reaction/electrophilic amination of acetaldehyde, leading to vicinal diamines. The third chapter studies a Michael reaction/electrophilic amination cascade, giving rise to hydrazinoaldehydes bearing a quaternary stereocenter. Finally, the last chapter focuses on the electrophilic amination of α,α-disubstituted aldehydes, and its application in an organocascade reaction, leading to 3-pyrrolines with a quaternary stereocenter
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Wolfe, John P. (John Perry) 1970. "Late transition metal catalyzed C-N and C-C bond forming reactions." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9521.
Full textAbstract:
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1999.Includes bibliographical references.
New methods for the palladium-catalyzed amination of aryl halides are described. Key to these is the development of new catalysts and reaction conditions for these transformations. Initially, P(o-tol)3 ligated palladium catalysts were investigated but gave way to systems that used chelating phosphine ligands which substantially expanded the scope of the catalytic amination methodology. Palladium catalyst systems based on BINAP ((2,2'-diphenylphosphino)-1, 1 '-binaphthyl) allowed for the transformation of a much wider range of amines and aryl halide substrates, as well as aryl triflates. Of practical significance was that the use of cesium carbonate as a base at 100 °C substantially increased the functional group tolerance of the method. Palladium catalysts supported by novel, bulky, electron-rich phosphine ligands are exceptionally effective in the C-N, C-0, and C-C coupling procedures. For some substrate combinations, these palladium catalysts are effective for the room-temperature catalytic amination of aryl chlorides. These palladium catalysts are also highly effective for Suzuki coupling reactions of aryl bromides and chlorides at room temperature. Suzuki coupling reactions of aryl bromides and aryl chlorides are effective at very low catalyst loadings (0.000001-0.005 mol % Pd for ArBr, 0.02-0.05 mol % for ArCI) at 100 °C, and reactions of hindered aryl halides or boronic acids are effected at moderate catalyst loadings (1 mol % Pd). The high reactivity of these catalysts towards aryl chlorides challenges the conventional dogma that chloride substrates cannot be transformed under mild conditions with palladium catalysts, and significantly expands the pool of substrates available for cross-coupling chemistry.
by John P. Wolfe.
Ph.D.
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Jäschke, Britta [Verfasser]. "Neue multinäre nitridische Keramiken in den Systemen B/P/N/(C), Al/P/N/(C) und Si/N/C aus molekularen und polymeren Vorläufern / Britta Jäschke." Aachen : Shaker, 2003. http://d-nb.info/1172611645/34.
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Treffert, Harald. "N,O- und N,C,N-koordinierte Platinmetallkomplexe : Synthesen, Strukturen und katalytische Anwendungen." kostenfrei, 2008. http://deposit.d-nb.de/cgi-bin/dokserv?idn=989135500.
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Monnehan, Georges. "Résonances dans les réactions nucléaires ¹⁵N + ¹²C et ¹⁵N +¹⁶O." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376081864.
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Ruiz-Castillo, Paula. "Palladium-catalyzed C-N and C-O cross-coupling reactions." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105048.
Full textAbstract:
Thesis: Ph. D. in Organic Chemistry, Massachusetts Institute of Technology, Department of Chemistry, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 375-410).
Chapter 1: This chapter describes a general method for the of the Pd-catalyzed N-arylation of hindered [alpha],[alpha],[alpha]-trisubstituted primary amines. The reaction utilized catalysts based on two biaryl phosphine ligands, which were developed via kinetics-based mechanistic analysis and rational design. These studies led to the first example of catalyst based on a hybrid (alkyl)aryl biaryl phosphine ligand that provides better results that its dialkyl- or diarylbiaryl analogues. The C-N coupling was efficient for a wide range of (hetero)aryl chlorides and bromides under mild conditions. Chapter 2: This chapter relates the development of the Pd-catalyzed C-O coupling of primary alkyl alcohols. The reaction of primary aliphatic alcohols bearing [beta]-hydrogen atoms can lead to undesired [beta]-hydride elimination pathways instead of the target reductive elimination from the [LPd(Ar)OAlk] intermediate, especially when using electron-rich aryl halides. Additionally, aryl chlorides have been shown to be more challenging coupling partners than the corresponding aryl bromides. The use of catalysts based on commercially available ligand t-BuBrettPhos and a novel hybrid ligand, AdCyBrettPhos, have allowed the C-O coupling reaction to proceed effectively at room temperature, minimizing the side reaction. A variety of functionalized primary alcohols have been successfully coupled with (hetero)aryl bromides and chlorides giving rise to medicinally interesting products. Chapter 3: This chapter is a compilation of the applications of Pd-catalyzed C-N coupling in various fields of chemical research since 2008. This work includes the reactions of nine classes of nitrogen-based coupling partners in the 1) synthesis of heterocycles, 2) medicinal chemistry, 3) process chemistry, 4) synthesis of natural products, 5) organic materials and chemical biology, and 6) synthesis of ligands. The large number of applications highlights the versatility and utility of this transformation both in academic and industrial settings.
by Paula Ruiz-Castillo.
Ph. D. in Organic Chemistry
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Le, Roux Anabel-Lise. "N-Myristoylation-Dependent c-Src Interactions." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/346927.
Full textAbstract:
c-Src is the leading member of the Src family of non-receptor tyrosine kinases, which are involved in many signaling pathways. Its deregulation affects cell migration, proliferation and survival. c-Src is composed of the intrinsically disordered N-terminal SH4 and Unique domains, of the folded SH3, SH2, kinase domains and of a C-terminal tail. c-Src is myristoylated at its N-terminal region and anchored to membranes via cooperative electrostatic and hydrophobic interactions. Weak interactions with lipids in the Unique and SH3 domains and intramolecular interactions between them were recently found in the non-myristoylated form. These interactions involve the Unique Lipid Binding region (ULBR) in the Unique domain, and the RT and nSrc loops in the SH3 domain. Our objective consisted in obtaining and characterizing the myristoylated form of the Unique and SH3 domains (MyrUSH3).
Protocols for the efficient production of myristoylated proteins were developed. The incorporation of shorter acyl chains was characterized as a general problem in the preparation of myristoylated proteins, and conditions enabling to minimize their formation were found, in particular in the case of expression in minimum media. A well-defined myristoylation-induced cleavage site was identified and characterized in the Unique Lipid Binding Region of the Unique Domain of c-Src. Conditions to obtain degradation-free samples for structural studies were established.
The kinetics of MyrUSH3 binding to liposomes was followed using surface plasmon resonance (SPR) and revealed two MyrUSH3 populations, a dominant form binding with relatively fast association and dissociation, and a minor persistently bound (PB) population not described earlier. This PB form was studied in an assay involving detection by a secondary antibody and the model better explaining the experimental results described these PB species to be dimer forms of MyrUSH3. In a construct in which the SH3 domain was replaced by the GFP protein, single molecule photobleaching experiments of these PB species bound to supported lipid bilayers were conducted. A major population of dimers over the bilayer surface was detected. When binding of the myristoylated SH4 (MyrSH4) peptide to liposomes by SPR, a PB population was also observed. Monitoring of the surface activity of MyrSH4 revealed the micelar behavior of the peptide at low concentrations.
Nuclear Magnetic Resonance (NMR) measurements permitted to study the effect of the myristoyl group on the intramolecular interactions between the Unique and SH3 domains, as well as on the binding of the ULBR and RT loops to liposomes when the protein was anchored in the
bilayer. 1H-15N spectra of the myristoylated Unique domain (MyrUSrc) confirmed the propensity of the ULBR to bind liposomes, but in a different manner depending on the nature of the lipid in the bilayer. These measurements of MyrUSrc also pointed out some intermolecular propensities in the MyrSH4 domain. 1H-15N spectra of MyrUSH3 in solution revealed the presence of a myristoyl binding site has been found in the RT loop. Interaction of the myristoyl chain with lipids results in the loss of other lipid binding interactions in the Unique and SH3 domains that were observed in the non-myristoylated form. The interaction between the SH4 and the SH3 domains that restricts the conformational space of the Unique domain was preserved in the myristoylated forms and in the presence of lipids.
The SPR and single molecule fluorescence studies revealed the formation of self-associated complexes of limited size upon binding of MyrUSH3 or MyrUGFP to liposomes, possibly driven by the presence of the MyrSH4 domain. The NMR data highlighted the interplay between the lipid binding regions of the Unique and SH3 domains, in presence or absence of liposomes. Therefore, the myristoylated intrinsically disordered Unique domain may act in c-Src regulation at the lipid bilayer interface.c-Src es miembro de una importante familia de tirosina quinasas, que está involucrada en la transducción de señales en las células. c-Src está formada por una región N-terminal desordenada (compuesta de los dominios SH4 y Único), por los dominios plegados SH3, SH2, SH1 (el dominio quinasa), y por una cola C-terminal. c-Src es una proteína miristoilada en su extremo N-terminal, lo cual permite su unión a membranas, unión reforzada por la interacción del dominio SH4 polibásico con los lípidos cargados negativamente. En ausencia del grupo miristoilo, se encontraron zonas de unión a lípidos y de interacciones intramoleculares en los dominios Único y SH3. El objetivo de este trabajo es la obtención y la caracterización de la forma miristoilada de los dominios Único y SH3 (MyrUSH3). Se desarrollaron protocolos que permitieron la producción de proteínas miristoiladas. La cinética de unión de MyrUSH3 a liposomas se estudió con resonancia de plasmones superficiales. Se observó una población mayoritaria con una asociación y una disociación relativamente rápidas, y una población minoritaria con una unión persistente a liposomas. Esta segunda especie se estudió por detección secundaria via un anticuerpo y se dedujo que estaba posiblemente formada por dímeros. El dominio SH3 se remplazó por una proteína verde fluorescente (MyrUGFP) y se estudió la unión de MyrUGFP a liposomas, mediante su observación con microscopía confocal, usando la técnica de fotoblanqueo de moléculas individuales. Se observó una población mayoritaria de dímeros. A continuación, se estudió la proteína MyrUSH3 con resonancia magnética nuclear, en solución o unida a liposomas. En solución, se encontró un sitio de unión al grupo miristoil en el dominio SH3. Tras la inserción del grupo miristoil en la bicapa lipídica, se perdió la capacidad de unión a lípidos en los dominios Único y SH3 (excepto el dominio SH4), y algunas interacciones intramoleculares fueron afectadas.
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Flournoy, Cecil Buford Jr. "N-parameter Fibonacci AF C*-Algebras." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/1221.
Full textAbstract:
An n-parameter Fibonacci AF-algebra is determined by a constant incidence matrix K of a special form. The form of the matrix K is defined by a given n-parameter Fibonacci sequence. We compute the K-theory of certain Fibonacci AF-algebra, and relate their K-theory to the K-theory of an AF-algebra defined by incidence matrices that are the transpose of K.
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Lee, Alison Victoria. "Catalyst and methodology development for regioselective C-N and C-C bond formation." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31377.
Full textAbstract:
The related investigations of catalytic hydroamination as a key step in synthetic methodology development and the synthesis of new hydroamination catalysts are reported in this thesis. The first section focuses on methodology development for the application of a bis(amidate)bis(amido) titanium hydroamination precatalyst towards the synthesis of functionalized small molecules via a tandem C-N, C-C bond forming reaction sequence. The development of two tandem sequential reactions will be described, as well as their applications in the synthesis of α-cyanoamines, α-amino acid derivatives, β-amino alcohols, diamines, imidazolidinones, and β-amino acid derivatives. These tandem reactions show an expanded substrate scope and increase synthetic flexibility by allowing for alternative starting materials in the preparation of highly functionalized small molecules. The second section describes progress towards the development of an asymmetric tandem reaction sequence, including investigations into the mode of activation for the tandem reaction. It has been established that a nucleophilic activation mode is required to generate an active species for the C-C bond forming step. Furthermore, it is postulated that the coordination environment and steric congestion about the activator impacts reaction efficiency and stereoselectivity. This information will be valuable in the design of future generations of activators. The final section reports the development of two novel group 4 metal complexes for catalytic hydroamination. The synthesis and full characterization of these complexes will be described, as well as the results of the catalytic investigations. Through this investigation it has been postulated that while a change in the electronic nature of the metal complex does enhance catalytic reactivity, the degree of orbital overlap between the ligand and the metal center is also an important consideration in the design of electrophilic hydroamination precatalysts. Hydroamination catalysis is currently an attractive area of intense research. The work in this thesis has demonstrated the use of hydroamination catalysis in the synthesis of highly functionalized small molecules, and has furthered the fundamental understanding of the hydroamination reaction. This increase in understanding can then be applied towards the rational design of more powerful hydroamination catalysts and further their application in the synthesis of functionalized N-containing compounds.Science, Faculty of
Chemistry, Department of
Graduate
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Graham, Alan. "New C-C and C-N bond forming reactions mediated by chromium complexation." Thesis, University of Bath, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760696.
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Barron, Benedict James. "Evaluation of asymmetric catalysts in C–C and C–N Michael type transformations." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/45060.
Full textAbstract:
The first chapter of this thesis presents a literature survey of recent developments in asymmetric C–C and C–N conjugate addition reactions using metal mediated and organocatalytic protocols, focusing on the limitations and strengths of each system. The aim of this study will also be presented. The second chapter discusses the study of two asymmetric Pd (II) catalytic protocols in the aza-Michael reaction of N-containing arylamines with N-carbamates. The main body of work focuses on the utilisation of N-protected phenylenediamine substrates. In one case, these nucleophilic amines are poorly tolerated, with an interesting deactivation pathway uncovered. For the second protocol, high yields and ee are achieved with an interesting water effect observed. The afforded aza-adduct substrates were subsequently cyclised into tetrahydroquinoline derivatives, with particular attention paid to the regioselectivity of the transformation. This chapter also highlights the limitations of ortho-substituted anilines under these two protocols. The third chapter highlights the attempts to further extend these aza-Michael Pd(II) catalysed protocols to the reactions of substituted hydroxylamines with N-carbamates, with the overall objective of furnishing enantio-enriched aziridine products. Variation of the Michael acceptor was also explored, focusing on the utilisation of α-substituted α,β-unsaturated 1,3-dicarbonyls and alkylidene malonates in the aza-Michael addition with simple aniline derivatives. In the fourth chapter, Pd(II) catalytic protocols are applied to the asymmetric C–C Michael addition of β-ketoester and β-ketoamides to β-substituted α,β-unsaturated thioesters with little success. In contrast, the employment of an asymmetric MBI-derived phase transfer organocatalyst in the Michael addition of glycine Schiff base with various oxo and thio-ester Michael acceptors provided facile access to chiral γ-lactam derivatives. Chapter 5 contains experimental procedures and characterisation data for all synthesised compounds.
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Kilaru, Praveen. "New Strategies for Transition Metal Catalyzed C-C and C-N Bond Formation." Diss., North Dakota State University, 2018. https://hdl.handle.net/10365/31710.
Full textAbstract:
Transition metal catalysis emerged as an essential tool in the field of organic chemistry. In this context, transition metal catalyzed C-H bond functionalization is considered as an alluring strategy as it occurs with the high atom-and-step economy. In the recent years, significant attention has been paid for the conversion of C-H bond into C-X (X = C, N, O, S, P..etc) bonds using transition metal catalysts. This thesis presents the development of new catalytic systems for the construction of C-C and C-N bonds through late transition metal-mediated C-H activation and decarboxylation reactions. Chapter 1 introduces the background of transition metal catalyzed C-H bond functionalization. This chapter provides reported catalytic methods for the conversion of arene C-H bonds into various functional groups through transition metal mediated chelation-assisted C-H bond activation.
Chapter 2 describes the development of a new method for the synthesis of oxindoles via intramolecular alkene hydroarylation with N-aryl acrylamides using a Ru(II)/N-heterocyclic carbene (NHC) catalyst system. This reaction occurs with good substrate scope and synthetically useful tolerance of functional groups and does not require the assistance of additional directing group. Preliminary mechanistic results support a tandem sequence involving amide-directed aromatic C-H bond activation and intramolecular alkene arylmetalation. Chapter 3 describes ruthenium-based decarboxylative alkenylation of heteroarenes through carboxylate directed C-H bond functionalization. The decarboxylative functionalization of heteroarenes occurs with high regioselectivity and a broad range of functional group tolerance. This decarboxylation proceeds without stoichiometric amounts of bases or oxidants and it is applicable for functionalization of various heteroarenes such as indole, pyrrole, thiophene, benzothiophene, and benzofuran at both C-2 and C-3 positions. The current protocol provides a straightforward approach for the synthesis of trisubstituted olefins with heteroarenes. Chapter 4 explains the development of Rh/Ag-bimetallic catalyst system for decarboxylative amidation of ortho-substituted benzoic acids with 3-aryldioxazolones. The nature of ortho-substituents determines regioselectivity of this reaction through two forms of proposed chelation assistance: (1) A wide range of non-directing ortho-substituents led to ortho-amidation products via carboxylate-directed C-H amidation and subsequent decarboxylation. (2) 2-Pyridyl and analogous DGs led to ipso-amidation products via DG-assisted decarboxylation and subsequent amidation.
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Bowen, John George. "C-H activation in the formation of C-N and C-O Bonds." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.685335.
Full textAbstract:
The regioselective activation of C-H bonds and subsequent transformation into desirable functional groupS is an attractive prospect in organic synthesis. We have developed two novel C-H functionalisation reactions; the first is an intramolecular, sulfonamide directed, C-H amination reaction for the synthesis of 3_phenylisoindolinone derivates and the second is a sulfonamide directed ortho C-H acetoxylation reaction. Both isoindolinones and phenol derivatives of sulfonamides are important motifs in numerous pharmaceutically relevant compounds. The Cull-catalysed intramolecular C-H amination reaction for the synthesis of substituted 3-phenylisolindolinone derivatives (Scheme i) was found to be tolerant to substitution on both aromatic rings, however, no reaction was observed on exchanging the tethered aryl group for an alkyl group. Mechanistic investigations revealed that C-H cleavage was not part of the rate-determining step which is likely to be coordination of the copper catalyst to the sulfonyl amide. Substitution of the tethered phenyl ring (R2 ) and a subsequent Hammett analysis indicated that this coordination may be accelerated by a cation-IT interaction between CU11 and the pie system of the aryl group.
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Enouz-Védrenne, Shaïma. "Elaboration et analyses structurales et chimiques de nanotubes hétéroatomiques de type C-N et C-B-N." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2007. http://tel.archives-ouvertes.fr/tel-00147980.
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Il existe actuellement deux structures nanotubulaires largement étudiées : les nanotubes de carbone (CNTs) possédant un gap de l'ordre de 1 eV et ceux de nitrure de bore (BN-NTs) dont le gap est compris entre 5 et 6 eV. Parvenir à doper ces nanotubes par substitution d'éléments chimiques pouvant introduire des états donneurs ou accepteurs est supposé être une approche prometteuse pour moduler les propriétés électroniques et optiques de ces nanostructures. Les objectifs de cette thèse ont été doubles. D'une part, il s'est agi de développer des procédés de synthèse modulables pour pouvoir produire différents types de tubes hétéroatomiques. La technique CVD assistée par aérosol et la technique de vaporisation laser ont été utilisées à cette fin. D'autre part, une analyse fine à l'échelle macroscopique et sub-nanométrique des échantillons a été réalisée principalement par microscopie électronique en transmission (HRTEM) et spectroscopie de pertes d'énergies des électrons résolue spatialement (SR-EELS).Il a ainsi été mis en évidence dans ce manuscrit la possibilité de réaliser des nanotubes de type CNx et CBxNy mono- et multi-feuillets. Par ailleurs, une forte tendance à la ségrégation en domaines de type C et BN a été observée avec un localisation préférentielle et une taille des domaine spécifique, fonction de la technique de synthèse utilisée.
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GERVAIS, CHRISTEL. "Etude par resonance magnetique nucleaire a l'etat solide de divers polymeres, precurseurs de ceramiques b-n, si-c-n, si-b-c-n et si-b-c-o." Paris 6, 1999. http://www.theses.fr/1999PA066210.
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L'elaboration de ceramiques a partir de precurseurs polymeres est une voie de synthese qui s'est beaucoup developpee recemment pour permettre l'elaboration de materiaux composites et remedier a la fragilite des ceramiques massives. Les grandes possibilites de mise en forme offertes par des polymeres solubles ou fusibles va en effet faciliter la fabrication de composites a renfort fibreux presentant d'excellentes proprietes mecaniques et qui trouvent par exemple leur application dans le secteur aeronautique et spatial. L'objet de ce travail est d'evaluer les potentialites qu'offre la rmn a l'etat solide pour caracteriser la conversion de precurseurs polymeres en ceramiques de type nitrure et borure. Cette voie d'elaboration conduit a l'obtention de composes complexes et peu organises dont la caracterisation structurale est relativement difficile. Toutefois, un reel developpement de ces procedes necessite une bonne comprehension des processus mis en jeu lors de la transformation du polymere en ceramique. Nous nous sommes interesses a differents polymeres preceramiques dans les systemes b-n, si-c-n, si-b-c-n et si-b-c-o : nous avons ete amenes a mettre en oeuvre differentes methodes rmn haute resolution a l'etat solide axees plus particulierement sur l'etude des noyaux 1 1b et 1 5n en essayant de contourner les difficultes afferentes a ces derniers (l'existence d'une interaction quadripolaire difficile a moyenner pour 1 1b et une tres faible sensibilite pour 1 5n). Nous avons d'une part tire profit de la presence de protons : elle a permis d'augmenter la sensibilite de spins peu abondants ( 1 3c, 1 5n et 2 9si) mais aussi de sonder l'environnement protone des differents noyaux etudies grace aux techniques de polarisation croisee. Les methodes les plus recents de rmn haute resolution des noyaux quadripolaires ont egalement ete mises en oeuvre (mq-mas, mas a hauts champs) afin d'apprehender les differents environnements du bore au sein d'une meme coordinence.
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Grünberg, Matthias F. [Verfasser], and Lukas [Akademischer Betreuer] Gooßen. "Nachhaltige Konzepte zur C-C, C-N und C-S Bindungsknüpfung / Matthias Grünberg. Betreuer: Lukas Gooßen." Kaiserslautern : Technische Universität Kaiserslautern, 2015. http://d-nb.info/1080521704/34.
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Wrigglesworth, Joseph W. "The development of new palladium(II) catalysed C-C, C-N and C-O bond formations." Thesis, University of Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601218.
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Cassirame, Bénédicte. "Couplages C-C utilisant des triarylbismuthines catalysés par le PEPPSI." Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1116.
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Les réactions de couplage métallocatalysées mises en avant par l'attribution du Prix Nobel de Chimie 2010 permettent la création de liaison C-C impossible par les réactions de type SN1 ou SN2. Or, les composés auxquels elles donnent accès sont très utilisés dans le domaine pharmaceutique, agrochimique ou encore dans celui de la chimie supramoléculaire. Si les réactions sont efficaces, les agents de couplages sont souvent peu accessibles et/ou peu éco(nomique/logique)-compatibles. Les triarylbismuthines lèvent en partie ces limitations, car tous les atomes de ces organométalliques participent aux processus et ces composés sont considérés comme non toxiques mais les réactions engageant ce type d'organométalliques souffrent de leur dimérisation. Afin de lever cette limitation, nous avons développé un système catalytique plus " vert" utilisant le PEPPSI comme pré-catalyseur sur une réaction test. Ces nouvelles conditions donnent généralement d'excellents rendements en série biarylique comme hétérobiarylique. La gamme des substituants sur le dérivé halogéné est très étendue mais plus limitée sur la bismuthine. Ce système catalytique a ensuite été utilisé sans modification dans les réactions domino d'élimination/couplage. Une étude cinétique comparative par GC/MS et RMN 13C a permis de montrer qu'une élimination d'ordre 2 avait lieu avant le couplage. De plus il y a un effet coopératif entre les ions fluorures et la bismuthine : celle-ci joue donc un double rôle : agent organométallique doux de couplage et base. L'ambiguïté mécanistique ainsi levée, il a été permis d'envisager une chimiosélectivité en fonction des divers états d'hybridation du carbone portant le brome au moment du couplage. Plusieurs méthodes d'accès à des molécules de structures Ar-Ar-C C-Ar à géométries variables peuvent être obtenues rapidement. Le système catalytique a également permet l'activation de liaison C-Br de bromocoumarines. Ainsi, il est possible de réaliser le couplage sur les positions 3-, 4- et 6-. L'ordre de réactivité a été déterminé ce qui a permis de réaliser des monocouplages parfaitement sélectifs sur les 3,4- ou 3,6- dibromocoumarines, dont les applications biologiques suscitent un grand intérêt. Le nouveau système catalytique a donc éliminé le problème de dimérisation des triarylbismuthines et donne potentiellement accès à des molécules intéressantes pour leurs propriétés physiques ou biologiquesMetallocatalysed crosscoupling reactions have been highlighted by the attribution of the 2010 Nobel Chemistry Price since they allow CC bond formation when classical SN1 or SN2 do not permit it. Furthermore, they give access to many pharmaceutics and agronomic compounds but also molecules used for their supramolecular properties. Nowadays, reactions are really efficient but reactants are not always readily accessible and can't be classified as green reagents. Since all its atoms act over the catalytic process and because they are not considered as toxic so far, triarylbismuthines may be a good alternative to circumvent the limitation described above. However, they suffer a main drawback, their reductive dimerisation. In order to avoid this side-reaction, a new greenest process has been developed on a benchmark reaction based on PEPPSI, an NHC/Pd catalyst. These conditions gave usually excellent yields, either for the biaryle or heterobiaryle crosscoupling reaction. The range of substituents is really wide on the aryle halide moiety but slightly more limited on the triarylbismuthine reagents. Then, this catalytic process has been applied without modification to an elimination/crosscoupling domino reaction. A GC/MS and 13C NMR supported comparative kinetic study showed that a 2nd order elimination take place before the C-C bond formation. Fluoride anion and triarylbismuthine act together. Therefore triarylbismuthine play a dual role: base and aryl transfer reagent. This mechanism study led to chimioselective reactions that allow many paths for the synthesis of Ar-Ar-C C-Ar containing compounds with a good control on geometry of this highly conjugated structure. This catalytic process allows also bromocoumarine C-Br bond activation. Thus, crosscoupling may be selectively performed at the 3-, 4- or 6- position of coumarines. The reactivity order difference of these positions even allow hightly selective mono crosscoupling reaction on 3,4- or 3,6-dibromocoumarines for further biological application. To conclude, our PEPPSI based greenest process avoid the dimerisation of bismuthines and give easy access to many compounds of great interest either for their biological or physical properties
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Owen, Gareth Richard. "Palladium-mediated transformationand activation of unsaturated C-N, C-S and C-O bonds." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408281.
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Frogneux, Xavier. "Transformations réductrices du CO2 pour la formation de liaisons C-N et C-C." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112136/document.
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Dans le monde actuel, le dioxyde de carbone (CO2) est le déchet majoritaire issu de l’utilisation des ressources fossiles mais il est encore peu utilisé dans les applications à grande échelle. Afin de tirer parti de son abondance, le développement de nouvelles transformations chimiques du CO2 pour accéder à des produits de chimie fine connait un intérêt croissant au sein de la communauté scientifique. Tout particulièrement, la formation de liaison(s) C-N à partir du CO2 et d’un substrat azotés permet d’accéder à des produits à hautes valeurs énergétiques et commerciales. Un second type de transformation désirable est la formation de liaison C-C à partir du CO2 afin de synthétiser des dérivés d’acides carboxyliques comme des esters. L’utilisation d’hydrosilanes, réducteurs doux, permet de travailler sous 1 bar de CO2 avec des catalyseurs à base de métaux peu coûteux et abondants tels que le fer et le zinc ou bien avec des organocatalyseurs. Les synthèses de formamides, de méthylamines ou d’aminals à partir du CO2 ont ainsi été développées par hydrosilylation. Enfin, la carboxylation des carbosilanes à partir du CO2 a été développée pour la première fois avec un catalyseur à base de cuivre. Dans le cas des 2-pyridylsilanes, l’utilisation de sels de fluorures pentavalents permet d’activer le substrat efficacement sans catalyseurIn the current world, carbon dioxide (CO2) is the major waste of the massive utilization of fossil resources but only few applications have been developed using this compound. In order to take advantage of its abundancy, the development of novel chemical transformation of CO2 to produce fine chemicals is of high interest in the scientific community. In particular, the formation of C-N bond(s) from CO2 and amine compounds unlocks a new way to access high energy and value-added. A second type of highly desirable transformation is the formation of C-C bonds with CO2 so as to synthesize carboxylic acid derivatives. The utilization of hydrosilanes as mild reductants allows the reactions to proceed under 1 bar of CO2 with abundant and cheap metal-based catalysts (iron, zinc) or with organocatalysts. The synthesis of formamides, methylamines and aminals from CO2 are described herein. Ultimately, the catalytic carboxylation of carbosilanes has been achieved for the first time using copper-based complexes. In the specific case of 2-pyridylsilanes, the use of pentavalent fluoride salts allowed us to perform the reaction without catalyst
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Sabour, Abdelouahed. "Étude expérimentale et thermodynamique de systèmes binaires des n-alcanes pairs-impairs (nc₂₃ : n-c₂₄ et nc₂₃ : c₂₂)." Vandoeuvre-les-Nancy, INPL, 1994. http://www.theses.fr/1994INPL064N.
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Dans les coupes pétrolières ou gazoles, le dépôt solide cristallise lors de baisses sensibles de la température est constitué en partie de solutions solides de n-alcanes. Compte tenu de la complexité de ces mélanges, la connaissance de leur comportement est nécessaire pour une analyse thermodynamique permettant d'approcher une modélisation du point de trouble des coupes pétrolières paraffiniques ou gazoles. Dans ce travail nous avons détermine les diagrammes de phases des deux systèmes binaires (nc₂₃: nc₂₄ nc₂₃: nc₂₂par l'utilisation conjointe de l'analyse thermique différentielle, de l'analyse enthalpimétrique, de l'analyse thermomécanique et de la diffraction des rayons X. Ceci nous a permis de mettre en évidence plusieurs phases intermédiaires et une systématique dans le comportement de n-alcanes pour les systèmes binaires pairs-impairs. L'étude thermodynamique comporte le représentation des mesures de la variation d'enthalpie en fonction de la température par un modèle du solide d'Einstein, les expressions analytiques des fonctions thermodynamiques sont exploitées pour le calcul des diagrammes de phases en représentant les grandeurs d'excès pour un modèle de margules à deux paramètres
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Hall, Jack Kingsbury Mathematics & Statistics Faculty of Science UNSW. "Some branching rules for GL(N,C)." Awarded by:University of New South Wales. Mathematics and Statistics, 2007. http://handle.unsw.edu.au/1959.4/29473.
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This thesis considers symmetric functions and algebraic combinatorics via the polynomial representation theory of GL(N,C). In particular, we utilise the theory of Jacobi-Trudi determinants to prove some new results pertaining to the Littlewood-Richardson coefficients. Our results imply, under some hypotheses on the strictness of the partition an equality between Littlewood-Richardson coefficients and Kostka numbers. For the case that a suitable partition has two rows, an explicit formula is then obtained for the Littlewood-Richardson coefficient using the Hook Length formula. All these results are then applied to compute branching laws for GL(m+n,C) restricting to GL(m,C) x GL(n,C). The technique also implies the well-known Racah formula.
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Damak, Mondher. "C*-algebres et probleme a n-corps." Cergy-Pontoise, 2000. http://www.theses.fr/2000CERG0091.
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Le but de cette these est l'etude par des methodes algebriques de certaines generalisations du probleme a n-corps. Notre point de vue est, au depart, celui des chapitres 8 et 9 de abg. Nous montrons dans un premier article (constituant le chapitre 2 de cette these) que les techniques abstraites developpees dans ce livre permettent de retrouver et d'ameliorer les resultats de c. Gerard sur les hamiltoniens dispersifs. Nous montrons aussi que le resultat de lewis, siedentop and vugalter concernant le spectre essentiel des systemes a n particules relativistes decoule facilement de la version algebrique du theoreme hvz de abg. Dans les chapitres 3 et 4 de la these nous allons au-dela du formalisme algebrique pour les systemes a n corps tel qu'il est expose dans le chapitre 9 de abg. Ces deux parties constituent en fait deux papiers en collaboration avec vladimir georgescu. Notre but est d'etudier des c*-algebres d'operateurs suggerees par le probleme a n corps mais en meme temps naturellement associees a des espaces vectoriels de dimensions finies, et de faire l'analyse spectrale des operateurs auto-adjoints qui leurs sont affilies. Cette classe d'operateurs est tres riche, elle permet par exemple de traiter de maniere unifiee les hamiltoniens des systemes dispersifs (avec des interactions dependantes du moment) et ceux des systemes stratifies ou pluristratifies. Abg w. Amrein, a. Boutet de monvel and v. Georgescu, c 0-groups, commutator methods and spectral theory of n-body hamiltonians (birkhauser, progress in math. Ser. Nr. 135, 1996).
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Nikolussi, Marc. "Cementite in the Fe-N-C system." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-38396.
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Anderson, Kevin William. "Expanding the substrate scope in palladium-catalyzed C-N and C-C bond-forming reactions." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36255.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2006.Vita.
Includes bibliographical references.
Chapter 1. The first detailed study of the palladium-catalyzed amination of aryl nonaflates is reported. Use of bulky electron-rich monophosphinobiaryl ligands or BINAP allow for the catalytic amination of electron-rich and -neutral aryl nonaflates with both primary and secondary amines. Using XantPhos, the catalytic amination of a variety of functionalized aryl nonaflates resulted in excellent yields of anilines; even 2-carboxymethyl aryl nonaflate is effectively coupled with a primary alkyl amine. Moderate yields were obtained when coupling halo-aryl nonaflates with a variety of amines, where in most cases the aryl nonaflate reacted in preference to the aryl halide. Overall, aryl nonaflates are an effective alternative to aryl triflates in palladium-catalyzed C-N bond-forming processes due to their increased stability under the reaction conditions. Chapter 2. A catalyst comprised of a Pd precatalyst and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl is explored in C-N bond-forming processes. This catalyst displayed unprecedented stability and scope allowing, for the first time, the coupling of substrates bearing a carboxylic acid or a primary amide.
(cont.) Also, the more bulky catalyst system Pd/2-tert-butylphosphino-2',4',6'-triisopropylbiphenyl was found to be effective for the Narylation of 2-aminoheterocycles and weakly basic HN-heterocycles: pyrazole and indazole. The chemoselectivity for amination using these catalysts was explored where the rough order of reactivity for amines is: aryl amines >> primary and secondary alkyl amines > 2-aminoheterocycles > primary amides - HN-heterocycles. Chapter 3. The palladium-catalyzed Suzuki-Miyaura coupling of haloaminoheterocycles and functionalized organoboronic acids using a highly active and stable monophosphinobiaryl ligand, 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, efficiently produced aminoheterocyclic biaryl derivatives. This same catalyst was effective in coupling 2-haloaminoaryl compounds with 2-formyl or 2-acetylphenyl boronic acids, providing the fused heterocyclic compounds phenanthridine, benzo[c][1 ,8]naphthridine and benzo[c][1,5]naphthridine in excellent yields. Chapter 4. A water-soluble monophosphinobiaryl ligand, sodium -dicyclohexylphosphino-2',6'-dimethoxybiphenyl-3'-sulfonate, was synthesized by electrophilic sulfonation of the lower-aromatic ring of 2-dicyclohexylphosphino-2',6'- dimethoxybiphenyl.
(cont.) This ligand was utilized in the palladium-catalyzed Suzuki-Miyaura reaction of water-soluble aryl/heteroaryl halides and organoboronic acids. The catalyst displays unprecedented reactivity and stability for Suzuki-Miyaura reactions conducted in water. Chapter 5. A water-soluble monophosphinobiaryl ligand, sodium 2'-(dicyclohexyl-osphanyl)-2,6-diisopropyl-biphenyl-4-sulfonate, was synthesized by a proposed electrophilic ipso-substitution/reverse Friedel-Crafts alkylation of the lower-aromatic ring on 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl. This ligand was utilized in the palladium-catalyzed Heck alkynylation (copper-free Sonogashira coupling) of hydrophobic and hydrophilic aryl halides and terminal alkynes conducted in an aqueous acetonitrile solvent system. For the first time, an electron-deficient terminal alkyne, propiolic acid, was successfully coupled with aryl bromides. We also demonstrated that this catalyst is useful in the reaction of benzyl chlorides and terminal alkynes to provide benzyl alkynes in good yields. We show that by using an excess amount of base (> 1.0 equiv.) and higher reaction temperatures ( 80 °C), base-catalyzed isomerization to the corresponding aryl allenes can be achieved in a one-pot process.
by Kevin W. Anderson.
Ph.D.
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Chudasama, V. "The use of aerobic aldehyde C-H activation for the construction of C-C and C-N bonds." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1324525/.
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This thesis describes a series of studies directed towards the use of aerobic aldehyde C-H activation for the construction of C-C and C-N bonds by the process of hydroacylation. Chapter 1 provides an introduction to the research project and an overview of strategies for hydroacylation. Chapter 2 describes the application of aerobic aldehyde C-H activation for the hydroacylation of vinyl sulfonates and sulfones. A discussion on the mechanism of the transformation, the effect of using aldehydes with different oxidation profiles and the application of chiral aldehydes is also included. Chapter 3 describes the functionalisation of γ-keto sulfonates with particular emphasis on an elimination/conjugate addition strategy, which provides an indirect approach to the hydroacylation of electron rich alkenes. Chapters 4 and 5 describe the application of aerobic aldehyde C-H activation towards the hydroacylation of α,β-unsaturated esters and vinyl phosphonates, respectively. An in-depth discussion on the mechanism and aldehyde tolerance of each transformation is also included. Chapter 6 describes acyl radical approaches towards C-N bond formation with particular emphasis on the synthesis of amides and acyl hydrazides.
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Baalbaki, Zein El-A. "Vibrational relaxation of N₄O, C₄H₄, and C₄H₄-Ar mixtures." Thesis, University of Ottawa (Canada), 1986. http://hdl.handle.net/10393/4666.
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Söllner, Johannes [Verfasser]. "C^C*-Cyclometallierende N-heterocyclische Carbenliganden in photophysikalisch aktiven Übergangsmetallkomplexen / Johannes Söllner." München : Verlag Dr. Hut, 2020. http://d-nb.info/1219477540/34.
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Persson, Andreas K. Å. "Palladium(II)-Catalyzed Oxidative Cyclization Strategies : Selective Formation of New C-C and C-N Bonds." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-75435.
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The main focus of this thesis has been directed towards preparation and oxidative carbocyclization of en-, dien- and aza-enallenes. In the first part of this thesis, a stereoselective oxidative carbocyclization of dienallenes was realized. By employing cheap and readily available palladium trifluoroacetate we were able to efficiently cyclize a variety of dienallenes into hydroxylated carbocycles in high yield and high selectivity. This oxidative process was compatible with two different reoxidation protocols: one relying on p-benzoquinone (BQ) as the oxidant and the other employing molecular oxygen as the oxidant. In the second part of the thesis the carbocyclization methodology was extended to include carbocyclization of aza-enallenes. This was achieved in two distinct steps. First, a copper-catalyzed coupling of allylic sulfonamides with bromoallenes was developed, giving access to the corresponding aza-enallenes. Subjecting these substrates to catalytic amounts of palladium acetate, along with BQ as the oxidant, rendered N-heterocycles in good yield. The reactivity of these N-heterocycles towards activated dienophiles was later exploited in a tandem (aerobic) oxidative carbocyclization/Diels-Alder reaction. The third topic involves efficient oxidative arylative/borylative carbocyclization of enallenes. These reactions, catalyzed by palladium acetate, relies on transmetallation of a (σ-alkyl)palladium(II) intermediate with diboranes or arylboronic acids. With this novel methodology we were able to obtain an array of arylated or borylated carbocycles, as single diastereomers, in high yield. Finally, we developed a palladium(II)-catalyzed cyclization of allylic carbamates. This mild, operationally simple, and scalable catalytic reaction opens up access to an array of oxazolidinones in high yield and excellent diastereoselectivity.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 6: Manuscript.
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Du, Wei, and 杜玮. "Palladium-catalyzed oxidative cascade cyclizations via C-N/C-C formation for synthesis of nitrogen heterocycles." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206320.
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Yang, Yang Ph D. Massachusetts Institute of Technology. "New reactivity and selectivity in transition metal-catalyzed C-C and C-N bond forming processes." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101558.
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Thesis: Ph. D. in Organic Chemistry, Massachusetts Institute of Technology, Department of Chemistry, 2015.Cataloged from PDF version of thesis. Volume 1 (page 1 to page 510) ; Volume 2 (page 511 to 881). Duplicated pages for pages 195 to 240 are bound after page 881.
Includes bibliographical references.
Part I. Palladium-Catalyzed Carbon-Carbon Bond Forming Cross-Couplings Chapter 1. Ligand-Controlled Palladium-Catalyzed Regiodivergent Suzuki-Miyaura Cross-Coupling of Allylboronates and Aryl Halides An orthogonal set of catalyst systems based on the use of two biarylphosphine ligands has been developed for the Suzuki-Miyaura coupling of 3,3-disubstituted and 3-monosubstituted allylboronates with (hetero)aryl halides. These methods allow for the regiodivergent preparation of either the ct- or the [gamma]-isomeric coupling product with high levels of site selectivity using a common allylboron building block. Preliminary investigations have demonstrated the feasibility of an enantioselective variant for the [gamma]-selective cross-coupling using chiral monodentate biarylphosphine ligands. Chapter 2. Palladium-Catalyzed Completely Linear-Selective Negishi Coupling of 3,3-Disubstituted Organozinc Reagents with Aryl and Vinyl Electrophiles A palladium-catalyzed general and completely linear-selective Negishi coupling of 3,3- disubstituted allyl organozinc reagents with (hetero)aryl and vinyl electrophiles has been developed. This method provided an effective means for accessing highly functionalized aromatic and heteroaromatic compounds bearing prenyl-type side chains. The utility of the current protocol was further illustrated in the concise synthesis of the anti-HIV natural product siamenol. Chapter 3. Palladium-Catalyzed Highly Selective Negishi Cross-Coupling of Secondary Alkylzinc Reagents with Aryl and Heteroaryl Halides The palladium-catalyzed Negishi cross-coupling of secondary alkylzinc reagents and heteroaryl halides with high levels of regioisomeric retention has been described. The development of a series of biarylphosphine ligands has led to the identification of an improved catalyst for the coupling of electron-deficient heterocyclic substrates. Preparation and characterization of oxidative addition complex (L)Pd(Ar)(Br) provided insight into the unique reactivity of palladium catalysts based on CPhos-type biarylphosphine ligands in facilitating challenging reductive elimination processes. Chapter 4. Mechanistic Studies on the Aryl-Trifluoromethyl Reductive Elimination from Pd(II) Complexes Based on Biarylphosphine Ligands A series of monoligated (L)Pd(Ar)(CF₃) (L = dialkyl biarylphosphine) have been prepared and studied in an effort to shed light on the mechanism of the aryl-trifluoromethyl reductive elimination from these systems. Combined experimental and computational investigations revealed unique reactivity and binding modes of (L)Pd(Ar)(CF₃) complexes derived from BrettPhos-type biarylphosphines. In contrast to a variety of C-C and C-heteroatom bond forming reductive eliminations, kinetic measurements showed this Ar-CF₃ reductive elimination is largely insensitive to the electronic nature of the to-be-eliminated aryl substituent. Furthermore, the aryl group serves as the nucleophilic coupling partner in this reductive elimination process. The structure-reactivity relationship of biarylphosphine ligands was also investigated, uncovering distinct roles of the ipso-arene and alkoxy interactions in affecting these reductive elimination reactions. Part II. Copper-Catalyzed Carbon-Carbon and Carbon-Nitrogen Bond Formation via Olefin Functionalization Chapter 5. Copper-Catalyzed ortho C-H Cyanation of Vinylarenes A copper-catalyzed regioselective ortho C-H cyanation of vinylarenes has been developed. This method provides an effective means for the selective functionalization of vinylarene derivatives. A copper-catalyzed cyanative dearomatization mechanism is proposed to account for the regiochemical course of this reaction. This mechanism has been validated through density functional theory calculations. Computational studies revealed that the high level of ortho selectivity in the electrophilic cyanation event originates from a unique six-membered transition state that minimizes unfavorable steric repulsions. Chapter 6. Regio- and Stereospecific 1,3-Allyl Group Transfer Triggered by a Copper-Catalyzed Borylation/ortho-Cyanation Cascade A copper-catalyzed borylation/cyanation/allyl group transfer cascade has been developed. This process features an unconventional copper-catalyzed electrophilic dearomatization followed by the subsequent regio- and stereospecific 1,3-transposition of the allyl fragment enabled by the aromatization-driven Cope rearrangement. This method provides an effective means for the construction of adjacent tertiary and quaternary stereocenters with high levels of stereochemical purity. Chapter 7. Copper-Catalyzed Asymmetric Hydroamination of Unactivated Internal Olefins: an Effective Means to Access Highly Enantioenriched Aliphatic Amines Catalytic assembly of enantiopure aliphatic amines from abundant and readily available precursors has long been recognized as a paramount challenge in synthetic chemistry. We describe a mild and general copper-catalyzed hydroamination that effectively converts unactivated internal olefins-an important yet unexploited class of abundant feedstock chemicals-into highly enantioenriched [alpha]-branched amines (>/= 96% ee) featuring two minimally differentiated aliphatic substituents. This method provides a powerful means to access a broad range of advanced, highly functionalized enantioenriched amines of interest in pharmaceutical research and other areas.
by Yang Yang.
Ph. D. in Organic Chemistry
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Aoki, Yuma. "Development of Iron-Catalyzed C-N and C-C Bond Forming Reactions toward Functional Arylamine Synthesis." Kyoto University, 2019. http://hdl.handle.net/2433/242518.
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Nasr, Allah Tawfiq. "Création de liaisons C-C et C-N par transformation catalytique du CO et du CO₂." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS607/document.
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Hormis la préparation de l’acide salicylique et de l’urée, peu de tentatives ont été réalisées jusqu’à présent pour promouvoir la formation de liaisons C–C et C–N à partir du CO₂. Cette thèse présente de nouveaux procédés catalytiques permettant la formation de molécules organiques azotées grâce à la création de liaisons C–N et C–C par transformation catalytique du CO et du CO₂. Les cibles retenues sont les amides ainsi que les alkylamines qui sont essentiels en chimie organique fine et sont souvent d’origine pétrosourcés. Dans un premier temps, la synthèse d’amide par carbonylation formelle de la liaison C–N d'amine sera étudiée grâce à des catalyseurs à base de métaux carbonyles. Dans un second temps, des procédés d’homologation des amines seront décrits grâce à l’utilisation de catalyseurs métalliques. La première stratégie impliquera l’utilisation de catalyseur de cobalt, en présence de CO et de silanes et permettra l’homologation sélective des liaisons N-méthyle en N-éthyle sous de faible pression de CO (P = 8 bar) et jusqu’au N-pentyle sous de fortes pressions. Dans un second temps, l’utilisation d’un catalyseur de ruthénium en présence d’un gaz de synthèse (CO/H₂) nous permettra de démontrer la possibilité de l’homologation de la diphénylamine. Enfin, la compréhension de ce système nous permettra de transposer cette réaction à l’utilisation du CO₂ comme substitut du COApart from the preparation of salicylic acid and urea, few attempts have been made so far to promote the formation of C-C and C-N bonds from CO₂. This thesis describes new catalytic processes allowing the formation of nitrogen compounds through the creation of C-N and C-C bonds by catalytic transformations of CO and CO₂. The chosen targets are the amides and the alkylamines which are essential in fine organic chemistry and yet prepared from petrochemicals. In a first part, the amide synthesis by formal carbonylation of the C-N bond HAS been studied using catalysts based on first row transition metal carbonyl complexes. In a second part, methods enabling homologation of amines are described through the use of metal catalysts. The first strategy involved the use of cobalt catalysts in presence of CO and hydrosilanes which allow the selective homologation of N-methyl into N-ethyl derivatives under a low CO pressure (P= 8 bar). Also, the alkyl chain can be homologated under elevated CO pressures to reach N-pentyl derivatives. Finally, the use of a ruthenium catalyst in presence of a synthesis gas (CO / H₂) allowed us to demonstrate the possibility of the homologation of the diphenylamine. Understanding this system led to translate the amine homologation with syngas to the use of CO₂ as a substitute for CO
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Haug, Jörg. "Untersuchung der Struktur und des Kristallisationsverhaltens von Si-C-N- und Si-B-C-N-Precursorkeramiken mit Röntgen- und Neutronenbeugung." [S.l. : s.n.], 2002. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10252174.
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Domínguez, Pérez Irene. "Catalizadores de oro y sus aplicaciones en reacciones de formación de enlaces C-C, C-N y C-O." Doctoral thesis, Universitat Politècnica de València, 2008. http://hdl.handle.net/10251/1983.
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Con objeto de encontrar nuevas aplicaciones catalíticas para el oro e incluso de mejorar los resultados alcanzados con catalizadores de este metal, se sintetizaron tres catalizadores de oro (III) partiendo de la sal NaAuCl4.2H2O y diversos ligandos quirales derivados de oxazolina. En las condiciones de síntesis, uno de los ligandos experimentó una apertura completa de ambos anillos de oxazolina, mientras que en los otros dos casos esta apertura fue parcial, perdiendo de esta forma la simetría C-2.
Por otro lado, se prepararon catalizadores de oro heterogéneos basados en nanopartículas de oro soportadas sobre el biopolímero quitosán, el cual fue depositado a su vez sobre sílice, obteniéndose dos catalizadores de oro con distinta relación biopolímero/sílice.
La actividad catalítica de los catalizadores sintetizados, homogéneos y heterogéneos, fue estudiada en la hidroaminación intermolecular de alquinos, así como en la epoxidación y ciclopropanación asimétrica de olefinas.
En la hidroaminación intermolecular de alquinos los catalizadores de oro fueron activos en ausencia de promotores, necesarios con el empleo de otros metales de transición. Los catalizadores basados en sílice-quitosán-oro no solo fueron más activos que otros catalizadores de oro conocidos, sino además los más estables pudiendo ser usados hasta seis veces sin pérdida de actividad.
En la epoxidación asimétrica de olefinas, los catalizadores de oro mostraron actividad con oxidantes clásicos como NaOCl y PhIO pero la velocidad de la reacción aumentó considerablemente cuando se incorporaba oxígeno molecular en el medio de reacción. Estudios mecanísticos pusieron de manifiesto un posible mecanismo dual para la reacción de transferencia de oxígeno. Se obtuvieron moderados valores de enantioselectividad. Los catalizadores heterogéneos pudieron ser utilizados cuatro veces sin pérdida de actividad.
Por último, en la ciclopropanación asimétrica de olefinas, el empleo de los catalizadores de oro condujo aDomínguez Pérez, I. (2007). Catalizadores de oro y sus aplicaciones en reacciones de formación de enlaces C-C, C-N y C-O [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1983
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Guti��rrez, Mart��nez Jezrael. "Produci��n y comercializaci��n de c��tricos naturales para hoteles y restaurantes." Thesis, Universidad de las Am��ricas Puebla, 2011. http://catarina.udlap.mx/u_dl_a/tales/documentos/lmas/gutierrez_m_j/.
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