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Henderson, William Howell. "Palladium-Mediated C-H Activations." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1318003095.
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Bechtoldt, Alexander. "Aerobic Ruthenium-Catalyzed C–H Activations." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E492-A.
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Korvorapun, Korkit. "Site-Selectivity in Ruthenium-Catalyzed C–H and C–C Activations." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-148C-7.
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Wang, Hui. "Cobalt(III)- and Manganese(I)-Catalyzed C-H and C-C Activations." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://hdl.handle.net/11858/00-1735-0000-002E-E5EF-5.
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Pal, S. "Non-metallic approaches for C-H and C-Si bond activations." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2013. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/1921.
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Korvorapun, Korkit [Verfasser]. "Site-Selectivity in Ruthenium-Catalyzed C–H and C–C Activations / Korkit Korvorapun." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1218299231/34.
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Tian, Cong. "Metallaelectro-Catalyzed C─H Activations by 3d Transition Metals." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1482-1.
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Mo, Jiayu. "Iron-Catalyzed C–H/N–H Activations for Annulation of Allenes, Alkynes, and Bicyclopropylidenes." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-14F0-5.
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Kossen, Hanno. "Exploration of Brønsted base catalysis for formal C–H bond activations." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/23598.
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This PhD project investigates the use of (Lewis or Brønsted) bases in catalysis. While the first chapter explores the use of main group metal amides in C–H bond activation reactions, the second chapter focusses on metal-free organocatalysis using so-called carbones. In the first chapter, formal allylic C(sp3)–H bond activations of unfuctionalised alkenes for C–C bond formations with imines were investigated. Alkali metal amides were used as catalysts for these transformations, giving homoallylic amine products. The investigations showed the unique reactivity of the Na-amide catalyst compared to other metal base complexes. The reaction scope and robustness was explored and initial insights into the reaction mechanism were obtained. A related K-amide catalyst was then developed for the isomerisation of allyl benzenes, as well as functionalised olefins such as allylic silanes, boronic esters, phosphines, amines, ethers, and thioethers. This part explored the use of ligands to increase the catalyst’s selectivity. Finally, the metal- or functional group-substituted classes of reagents were used in the functionalised allylation of imines, giving highly complex molecules with a diverse range of applications. Here, unprecedented reactivities were observed for the use of allyl–M reagents, as the allylation involved the activation of C–H bonds rather than C–X bonds. Furthermore, new catalytic formations of heteroatom-substituted homoallylic amines were described. The following chapter focussed on the use of carbodiphosphoranes (CDPs) in catalysis. These C(0) bases, or carbones, represent a class of heteroallene compounds that exhibit a high electron density on a P(V)-flanked carbon centre. Their potential as either a Lewis or Brønsted base was examined. Different CDPs were synthesised and reacted stoichiometrically with CO2, boron Lewis acids and metal salts. The generated intermediates were then studied in their reaction behaviour, taking advantage of a potentially available second pair of electrons. The results of these reactions were compared to other carbon bases, such as carbenes or other carbones. Finally, the Brønsted basicity of the CDP was examined in reactions with acidic pro-nucleophiles. The conjugate addition of alkylnitriles to α,β- unsaturated amides was developed using a catalytic amount of CDP. To the best of our knowledge, the first catalytic use of a CDP, as well as the first C–H bond activation of acetonitrile in Michael additions was reported.
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Tian, Cong [Verfasser]. "Metallaelectro-Catalyzed C─H Activations by 3d Transition Metals / Cong Tian." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1217842853/34.
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Dhawa, Uttam [Verfasser]. "Resource-Economical Synthesis by Selective Metal-Catalyzed C–H Activations / Uttam Dhawa." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1233008986/34.
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Mo, Jiayu [Verfasser]. "Iron-Catalyzed C–H/N–H Activations for Annulation of Allenes, Alkynes, and Bicyclopropylidenes / Jiayu Mo." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1221802356/34.
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Amistadi-Revol, Hugo. "Fonctionnalisations régiosélectives des naphtalènes via des activations C-H : nouvelles méthodologies et applications en synthèse." Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAE014.
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Cette thèse traite des réactions d'activations C-H régiosélectives sur le naphtalène. L'objectif est de développer plusieurs méthodologies pouvant être impliquées en synthèse de produits d'intérêt.Le premier projet de cette thèse a permis de fonctionnaliser des 1-carbonyl-naphtalènes en réalisant des fluoroalkylations et des fluoroalcénylations en position C8 par activation C-H, catalysée par du palladium. Divers groupements directeurs ont été employés, et il a été mis en évidence que l'amide méthylique et la cétone méthylique sont les meilleurs candidats pour ce type de réactivité. Le potentiel de ces réactions a permis de synthétiser de nombreux exemples variés en termes de fonctions chimiques et de positionnement des fonctions évaluées sur le cycle du naphtalène.Le second projet a établi les conditions pour diverses halogénations du 1-naphtaldéhyde par activation C-H, également catalysées par du palladium. Nous avons trouvé des conditions permettant une activation régiosélective, soit en C2, soit en C8. Bien que l'étendue de la tolérance de cette méthode soit plus limitée que celle du premier projet, il a été possible de réaliser diverses applications, permettant la synthèse de squelettes de produits d'intérêt.Pour finir, nous avons appliqué la méthode d'halogénation en C8 du 1-naphtaldéhyde à la synthèse d'une librairie de naphtolactames. Ces substrats ont été évalués dans le cadre de tests biologiques contre la bactérie Pseudomonas aeruginosa. En parallèle, cette méthode a été employée dans la synthèse d'un produit naturel : l'aspergilline F, obtenue en 7 étapes à partir du 1-naphtaldéhyde correspondantThis thesis deals with regioselective C-H activation reactions on naphthalene. The objective is to develop several methodologies that can be applied in the synthesis of products of interest.The first project of this thesis enabled the functionalization of 1-carbonyl-naphthalenes by performing fluoroalkylations and fluoroalkenylations at the C8 position through C-H activation, catalyzed by palladium. Various directing groups were employed, and it was found that the methylene amide and methylene ketone are the best candidates for this type of reactivity. The potential of these reactions allowed the synthesis of numerous examples varied in terms of chemical functions and positioning on the naphthalene ring.The second project established the conditions for various halogenations of 1-naphthaldehyde through C-H activation, also catalyzed by palladium. We found conditions allowing for regioselective activation, either at C2 or C8. Although the scope of this method's tolerance is more limited than the previous one, it was possible to achieve various applications, enabling the synthesis of skeletons of products of interest.Finally, we applied the C8 halogenation method of 1-naphthaldehyde to the synthesis of a library of naphtholactams. These substrates were evaluated in biological tests against the bacterium Pseudomonas aeruginosa. In parallel, this method was employed in the synthesis of a natural product: aspergilline F, obtained in 7 steps from the corresponding 1-naphthaldehyde
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Wang, Hui [Verfasser], Lutz [Akademischer Betreuer] Ackermann, Lutz [Gutachter] Tietze, Alexander [Gutachter] Breder, Manuel [Gutachter] Alcarazo, Dietmar [Gutachter] Stalke, and Shoubhik [Gutachter] Das. "Cobalt(III)- and Manganese(I)-Catalyzed C-H and C-C Activations / Hui Wang ; Gutachter: Lutz Tietze, Alexander Breder, Manuel Alcarazo, Dietmar Stalke, Shoubhik Das ; Betreuer: Lutz Ackermann." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1182033644/34.
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Bechtoldt, Alexander [Verfasser], Lutz [Akademischer Betreuer] Ackermann, Lutz [Gutachter] Ackermann, Konrad [Gutachter] Koszinowski, Manuel [Gutachter] Alcarazo, Dietmar [Gutachter] Stalke, Franziska [Gutachter] Thomas, and Max [Gutachter] Hansmann. "Aerobic Ruthenium-Catalyzed C–H Activations / Alexander Bechtoldt ; Gutachter: Lutz Ackermann, Konrad Koszinowski, Manuel Alcarazo, Dietmar Stalke, Franziska Thomas, Max Hansmann ; Betreuer: Lutz Ackermann." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1166399796/34.
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Ren, Hongjun. "Preparation of Condensed N-Heterocycles via Chemoselective Benzylic C-H Activations and Preparation of Alkenylmagnesium Reagents, Allylic Zinc Reagents and their Applications in Organic Synthesis." Diss., lmu, 2006. http://nbn-resolving.de/urn:nbn:de:bvb:19-62454.
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Hebert, Alexandra. "Mise au point de nouvelles techniques de radio-iodation et application au radiomarquage de molécules d'intérêt." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC413/document.
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Le radiomarquage de molécules d’intérêt avec des isotopes radioactifs est d'un grand intérêt pour la communauté scientifique, car il influe fortement sur le processus de découverte dans les sciences de la vie et en médecine nucléaire. Les molécules radiomarquées ont été largement utilisées pour évaluer les réactions biochimiques, pour mesurer la distribution in vivo d'une substance ou pour réaliser des tests RIA (RadioImmunoAssay). En médecine nucléaire, des radiopharmaceutiques pour la thérapie par ra-dio-isotopes (RIT) et des radiotraceurs pour des expériences d'imagerie telles que la TEP (tomographie par émission de positons), la tomographie par émission monophotonique (TEMP) ou la scintigraphie ont été décrites. Plusieurs isotopes de l'iode peuvent être utilisés à la fois pour le diagnostic et le traite-ment : 123I pour l'imagerie TEMP, 124I pour la TEP, 125I pour l'analyse biologique et 131I pour la radio-thérapie et la scintigraphie.Les méthodes classiques de radio-iodation reposent sur l'utilisation d'un précurseur pré-fonctionna-lisé, qui doit être synthétisé, isolé et purifié avant d'être introduit à l'étape de radio-iodation. La méthode par radioiododéstannylation est la méthode la plus populaire, bien que les précurseurs stannylés soient connus pour leur synthèse difficile et leur toxicité. Le développement de nouvelles méthodes de radio-iodation représente donc un grand intérêt dans le domaine de la radiochimie.Sur la base de travaux antérieurs, notre groupe a mis au point une méthode de radio-iodation de N-acylsulfonamides au moyen d’une radio-iodation C-H médiée par le palladium à température ambiante. Cette stratégie originale permet le radiomarquage de molécules d’intérêt dans des conditions très douces sans utiliser de précurseurs chimiques.Sur la base de la littérature, notre groupe développe actuellement une nouvelle méthode de radio-iodation de dérivés d’arylsilanes par radioiododésilylation dans des conditions douces. Cette méthodo-logie générale permet pour le moment le radiomarquage de dérivés d'arylsilanes activés en conditions doucesLabeling of (bio)molecules with radioactive isotopes is of high interest to for the scientific commu-nity, as it strongly impacts the discovery process in life science and nuclear medicine. Radiolabeled molecules have been extensively used to assess biochemical reactions, to measure in vivo distribution of a substance or to preform RIA (RadioImmunoAssay). In nuclear medicine, radio-therapeutics for RIT (RadioIsotope Therapy) and radio-tracers for molecular imaging experiments such as PET (Positron Emission Tomography), SPECT (Single Photon Emission Computed Tomography) or scintigraphy have been described. Several useful isotopes of iodine can be used for both diagnosis and therapy: 123I for SPECT imaging, 124I for PET imaging, 125I for biological assays and 131I for radio-therapy and scintig-raphy.Classical methods of radioiodination methods use a prefunctionalized precursor, which must be syn-thesized, isolated and purified before being introduced to the radio-iodination step. The radioiodode-stannylation method is the most popular method, although stannylated precursors are known for their difficult synthesis and their toxicity. The development of new methods of radioiodination is therefore of great interest in the field of radiochemistry.Based on a previous work, our group has developed a method to radio-iodinate N-acylsulfonamides through a room temperature palladium mediated C-H radio-iodination. This original strategy allows radiolabeling of biomolecules in very mild conditions without the use of chemical precursors.Based on literature, our group is now developping a new method to radio-iodinate arylsilyl derivates through radioiododesilylation in mild conditions. This general methodology allows for the moment the radiolabeling of activated arylsilyl derivates in mild conditions
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Weeks, Amanda. "C-H activation in organic synthesis." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.535205.
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Doyle, Claire Marie. "C-H activation reactions of tetrahydropyridines." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9469.
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This thesis is presented as five chapters: Chapter 1.0 is divided into two sections: the first is a review of palladium-catalysed C–C bond forming reactions. It covers palladium-catalysed cross-coupling reactions; C–H bond functionalisation; the Heck reaction and functionalisation of heteroaromatic C–H bonds. Secondly the use of tetrahydropyridines in organic synthesis is discussed, with a particular focus on methodology developed by the Craig group. Chapter 2.0 discusses the research carried out during this studentship. It is divided into six sections and discusses the results obtained from research efforts into: our initial strategy for tetrahydropyridine synthesis; an SN1 approach; an α,β-unsaturated lactam approach; synthesis of 3-methoxy aryl-substituted tetrahydropyridines; synthesis of heteroaromatic analogues and further elaboration of tricyclic tetrahydropyridines. Chapter 3.0 details future work proposed within the areas described above. Chapter 4.0 details the experimental procedures employed and spectroscopic data for the compounds discussed in chapter 2.0. Finally, chapter 5.0 lists the references sourced in this thesis.
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Di, Matteo Marco. "Selective C-H Activation of Terpenes." Electronic Thesis or Diss., Sorbonne université, 2024. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2024SORUS001.pdf.
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Ce travail de thèse porte sur la découverte de nouvelles stratégies pour l'activation/fonctionnalisation C-H des terpènes, avec un accent particulier sur le (+)-limonène et la catalyse au palladium. Tout d'abord, nous avons décrit le couplage C(sp2)-H/C(sp2)-H déshydrogénant catalysé par le Pd(II) entre le limonène et des alcènes pauvres en électrons, avec une extension à divers terpènes et terpénoïdes. Ensuite, nous avons étudié la post-fonctionnalisation d'un produit issu du couplage déshydrogénant développé et de l'éthynylbenzène en conditions micellaires. Par la suite, nous avons développé avec succès le couplage redox neutre C(sp2)-H/C(sp2)-X entre le (+)-limonène et des bromoalcènes. Cette stratégie, qui est complémentaire par rapport au couplage déshydrogénant, nécessite une charge plus faible du catalyseur au palladium et du sel d'argent par rapport au couplage étudié précédemment. Enfin, nous avons étudié de nouvelles approches pour la synthèse du cannabidiol (CBD). Des travaux futurs seront nécessaires pour évaluer les stratégies et atteindre la cible synthétiqueThis thesis work is dealing with the discovery of new strategies for the C-H activation/functionalization of terpenes, with particular emphasis on (+)-limonene and palladium catalysis. Firstly, we described the dehydrogenative Pd(II)-catalyzed C(sp2)-H/C(sp2)-H coupling between limonene and electron-poor alkenes, with extension to various terpenes and terpenoids. Therefore, we studied the post-functionalization of one product stemming from the dehydrogenative coupling and ethynylbenzene under micellar regime. Secondly, we successfully developed the Pd(II)-catalyzed redox neutral C(sp2)-H/C(sp2)-X coupling between (+)-limonene and bromoalkenes. This strategy, which is complementary with respect to the dehydrogenative coupling, needs a lower loading of the palladium catalyst and of the silver salt with respect to the previously studied coupling. Finally, we investigated the study of new approaches to cannabidiol (CBD). Of course, future work will be necessary to evaluate the strategies and reach the target
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Zhang, Shoukun. "Selective C–H Activation by Ruthenium(II) Carboxylate and Nickelaelectro-Catalysis." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://hdl.handle.net/21.11130/00-1735-0000-0005-155B-E.
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Pierre, Cathleen. "Synthèses de molécules polycycliques par arylation C(sp³)-H intramoléculaire catalysée par le palladium." Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00975446.
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La synthèse de produits complexes se doit de prendre en compte de nouvelles méthodes desynthèse plus efficaces, dont la fonctionnalisation de liaisons carbone-hydrogène. Dans cecontexte, la catalyse homogène par les métaux de transition s'est avérée performante, tout encontrôlant la régio- et la chimiosélectivité de la réaction. Les travaux de thèse présentés dansce manuscrit témoignent de l'efficacité de cette stratégie pour la construction rapide decomplexité moléculaire.Dans un premier temps, nous nous sommes intéressés à l'utilisation de précurseurs chlorés, cequi a permis d'étendre significativement le champ d'application de l'arylation C(sp3)-Hintramoléculaire pallado-catalysée. Ces travaux ont conduit à la synthèse de nombreuxhétérocycles, difficilement accessibles par d'autres voies de synthèse plus traditionnelles.Dans un deuxième temps, le développement d'une méthodologie de double arylation C-Hnous a permis de synthétiser des molécules polycycliques aux squelettes originaux. Une seuleet même espèce catalytique permet dans ce cas de réaliser les deux opérations d'activation CHavec succès.Par la suite, nous avons montré qu'il était possible de synthétiser des composés énantioenrichispar arylation C(sp3)-H intramoléculaire asymétrique. Pour cela, les ligands chiraux detype phosphépine se sont avérés particulièrement performants, et induisent desénantiosélectivités prometteuses.Enfin, notre attention s'est portée vers la synthèse de polycycles par arylation C(sp3)-Hintramoléculaire deshydrogénante. Les résultats encourageants obtenus apparaissent commeune preuve de concept dans ce domaine, où très peu de travaux de recherche ont été rapportés.
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Moselage, Marc Philipp. "C-H and C-C Activation by Cobalt and Ruthenium Catalysis." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2017. http://hdl.handle.net/11858/00-1735-0000-0023-3FB2-6.
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Vastine, Benjamin Alan. "Understanding mechanisms for C-H bond activation." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2679.
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Khamker, Qudsia. "Ambiphilic C-H activation routes to heterocycles." Thesis, University of Leicester, 2014. http://hdl.handle.net/2381/28919.
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This thesis describes investigations of Cp*Rh- and (p-Cy)Ru-catalysed C-H functionalisation reactions of various substrates with alkynes and alkenes for the formation of several heterocycles and carbocycles. Mechanistic studies and DFT calculations are also presented. Chapter One includes a discussion of different mechanisms of C-H activation namely oxidative addition, σ-bond metathesis, 1,2-addition, electrophilic activation and AMLA/CMD. The applications of these different mechanisms of C-H activation in catalysis are also discussed with a particular emphasis on the use of AMLA/CMD in direct arylation reactions. Chapter Two gives an overview of stoichiometric and catalytic studies of AMLA C-H activation and subsequent reactivity with alkynes at Ir, Rh, and Ru. The results of Cp*Rh- and some (p-Cy)Ru-catalysed reactions of C-phenylpyrazoles with alkynes are presented. N-H and C-H activation occurs, leading to heterocycles. Mechanistic studies and DFT calculations show that C-H activation is reversible and rate limiting in the cases examined. Chapter Three is similar to Chapter Two but focusses on reactions with alkenes. The Cp*Rh-catalysed reactions of C-phenylpyrazoles with alkenes lead to mono or divinyl products which may undergo further aza-Michael cyclisations if the alkene is a good Michael acceptor. Mechanistic studies and DFT calculations are also discussed. Chapter Four deals with Cp*Rh-catalysed coupling reactions of other directing groups, including imidazole, imidazoline, pyrazolidinone, hydrazine, carboxylic acid and oxime with alkynes. Again, there is discussion on the different factors affecting product selectivity. Chapter Five gives a summary of all the conclusions on the work presented in this thesis. Throughout the thesis, all new compounds are characterised spectroscopically and several compounds have been characterised by X-ray crystallography.
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Wiley, Jack Scott. "C-H bond activation in iridium complexes /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/8510.
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Bu, Qingqing. "Ruthenium- and Cobalt-Catalyzed C-H Activation." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E4FC-F.
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Coxon, Thomas. "Investigating rhodium-catalysed hydroacylation and carbon-carbon bond activation." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:26111304-1563-4c18-956e-67636b87983a.
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The work described in this thesis documents the development of new rhodium(I)-catalysed methodologies within two areas of research. The first examines the use of carbonyls as chelating groups in hydroacylation to produce synthetically valuable ketones and enones. The second area explores new carbon-carbon bond activation methodologies. Chapter 1 presents a literature review of the historical development of rhodium-catalysed hydroacylation, with a focus on chelating groups that can currently be used to suppress decarbonylation. A brief review of methodologies that avoid the requirement for a tether is also included. Chapter 2 describes the development of a novel hydroacylation methodology employing carbonyl-based functional groups as tethers on aldehyde substrates. The chapter begins with the optimisation studies for the hydroacylation of β-formyl amides with terminal and internal alkynes, allenes and terminal alkenes, and subsequently explores the substrate scope for each case. The chapter then outlines the investigations undertaken with 1,4-dicarbonyl and 1,5-dicarbonyl systems, N-formyl amides, β-formyl esters and finally β-formyl ketones. A detailed description of the routes undertaken to synthesise each starting material is also presented. Chapter 3 presents a short review surveying the key milestones in the development of carbon-carbon activation methodologies. The chapter begins with a theoretical comparison to carbon-hydrogen activation and a discussion of the unique challenges that are faced. An overview of the major strategies employed to enact these processes is subsequently presented for both strained and unstrained substrates. Chapter 4 outlines the attempts undertaken to develop a novel carbon-carbon bond activation methodology. The work evaluates sulfur-, nitrogen- and alkene-based chelating groups, known to be successful in hydroacylation, in analogous ketone substrates. Chapter 5 discusses the conclusions from this work and the potential for further work. Chapter 6 presents the experimental procedures and data.
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Palazzolo, Alberto. "Development of new methods for the hydrogen isotope exchange catalyzed by metallic nanoparticles." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS276.
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Les composés marqués aux isotopes de l’hydrogène possèdent des nombreuses applications lors des phases précliniques de développement des médicaments. Par exemple, les composés deutérés sont utilisés comme étalons internes dans la quantification par LC-MS de métabolites alors que les molécules tritiées sont souvent des radiotraceurs de choix dans les études d’absorption, distribution, métabolisme et excrétion (ADME) moléculaire des candidats médicaments. Après une brève introduction, un premier chapitre discutera du développement d’une méthode douce et sélective, catalysée par des nanoparticules de ruthénium, qui permet d’effectuer le marquage en une étape de bases azotées et de médicaments dérivés. En changeant le ligand qui stabilise le nanocatalyseur, on a réalisé des échanges isotopiques compliqués tels que des tritiations en utilisant une pression sous-atmosphérique de tritium gaz et des deutérations d’oligonucleotides sensibles. Le chapitre suivant décrira la modification des catalyseurs commerciaux à base de ruthénium grâce à la coordination de carbènes N-hétérocycliques (NHCs). La modification assure une régio- et une chimiosélectivité améliorées lors de la deutération d’alcools aliphatiques. Certains des catalyseurs modifiés ont permis l’échange hydrogène/deutérium sur des molécules, particulièrement sensibles à la réduction, qui n’ont pas pu être isolées en utilisant le catalyseur commercial. Dans le dernier chapitre, la synthèse et l’évaluation de l’activité catalytique des nanoparticules à base d’iridium seront discutées. Ces nanocatalyseurs ont démontré une réactivité intéressante dans le marquage des composés complexes. Dans certains cas, les nanoparticules d’iridium ont permis l’incorporation de deutérium sur des positions inhabituelles en comparaison avec d’autres réactions d’échange isotopique déjà décritesHydrogen isotopes labelled compounds possess a broad range of application in the early pre-clinical phases of drug development process. For instance, deuterated compounds are applied as internal standard in quantitative LC-MS techniques while tritiated molecules are often the preferred radioactive tracers for the study of molecular absorption, distribution, metabolism and excretion (ADME). After a brief introduction, a first chapter will discuss the development of a mild and selective method to perform late stage labelling of variously functionalized nucleobases and drug analogues catalyzed by ruthenium nanoparticles. By changing the ligand which stabilizes the nanocatalyst, we achieved challenging isotopic exchanges such as tritiations of pharmaceuticals using subatmospheric pressure of tritium gas and deuteration of sensible oligonucleotides. The next chapter will describe the modification of commercially available ruthenium nanocatalysts via the coordination of N-Heterocyclic carbenes (NHCs). The modification granted enhanced regio and chemoselectivity for the deuteration of aliphatic alcohols. Some of the modified ruthenium catalysts allowed the hydrogen/deuterium exchange on easily reducible compounds which were not obtainable using the unmodified commercial catalyst. The final chapter will discuss the synthesis and the evaluation of the catalytic activity of iridium nanoparticles. The latter, showed an interesting reactivity for the labelling of challenging substrates. In some of the investigated compounds, IrNps were able to introduce deuterium with unusual regioselectivities compared to already described hydrogen isotope exchange reactions
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Torkelson, Jeffrey Robert. "C-H bond activation and C-C bond formation at adjacent metals." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ34848.pdf.
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Chow, Catherine. "C-H activation by a tungsten trimethylsilylallyl complex." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42646.
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Thermolysis of Cp*W(NO)(Np)(η³-CH₂CHCHSiMe₃) generates a 16-electron allene
intermediate complex that selectively activates hydrocarbons at their methyl groups. In the
case of linear alkanes, only terminal activation is observed. This selectivity persists in the
presence of an ether functionality, but not of other oxygen-containing substrates such as
aldehydes and alcohols. With these latter substrates, oxidation of the complex to
Cp*W(O)₂Np has been noted. The existence of the allene intermediate has been verified by
two thermolytic experiments, and kinetic studies show that Cp*W(NO)(Np)(η³-
CH₂CHCHSiMe₃) is consumed according to pseudo-first-order kinetics during C–H bond
activation. The neopentyl ligand can be functionalized by reaction with CO, and the resulting
acyl complexes undergo chemical exchange on a slow timescale. The congeneric Mo
complex has also been synthesized, and although this complex is equally capable of
generating the η²-allene intermediate, its preferred mode of reactivity is coupling of the allyl
and alkyl ligands. As a result, the Mo complex is inferior to the W system for C–H
activation.
The thermolysis of Cp*W(NO)(Np)(η³-CH₂CHCHSiMe₃) in benzene has been
studied since the major products of this reaction each contain a 1,3-disubstituted allyl ligand
which might reduce reactivity at the allyl ligand in subsequent chemistry. In thermolytic
conditions, the resulting disubstituted allyl hydride complex undergoes no apparent reaction
with alkanes, but with deuterobenzene, deuterium incorporation into the allyl ligand is
observed. In addition to H/D exchange, the hydride ligands in these complexes can also migrate onto the allyl ligand, forming an η²-olefin complex that can be trapped as the
pyridine adduct.
The activation of fluorobenzenes by Cp*W(NO)(Np)(η³-CH₂CHCHSiMe₃) was also
studied, and in these substrates, exclusive activation of the C–H bond is observed. Migration
of the newly formed aryl ligands onto the allyl ligand does not occur when there is a fluorine
atom in the ortho position, which is probably due to the reduced nucleophilicity of the ligand
relative to the unfluorinated phenyl ligand. Selectivity in the activation of C–H bonds in
fluorobenzenes appears to be determined by sterics.
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Luo, Junfei. "Controlling regioselectivity and enantioselectivity in C-H activation." Thesis, Queen Mary, University of London, 2015. http://qmro.qmul.ac.uk/xmlui/handle/123456789/9550.
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The direct functionalisation of C-H bonds has emerged in recent years as an efficient and atom-economic alternative to the traditional cross coupling reaction. One of the challenges towards this goal is the selective transformation of a particular C-H bond amongst many other C-H bonds. This thesis describes studies on the use of CO2 as a traceless promoter for controlling meta-regioselective arylation of phenols and a separate investigation into an enantioselective arylation of pre-chiral η6-arene tricarbonyl chromium complexes. The introduction provides a general review of recent advances in the use of coordinating moieties as directing groups for selective activation of aromatic C-H bonds. The challenge of meta-selective C-H activation and the direct functionalisation of phenols is assessed and discussed. To overcome the scarce methods for accessing meta-arylated phenols, our objective was to develop an efficient methodology for the meta-arylation of phenols. Our strategy includes an ortho-carboxylation of the phenol followed by ortho-arylation of the salicylic acids and the subsequent protodecarboxylation to afford meta-arylphenols is proposed. A step-wise approach towards our aim is applied. First, a convenient and efficient method for the carboxylation of phenols is presented in Chapter 2. Then, a tandem arylation/decarboxylation reaction of salicylic acids is described in Chapter 3. Last, an efficient methodology for the meta-arylation of phenols via carboxylation/arylation/ decarboxylation processes in one-pot is presented in the following section in Chapter 3. To demonstrate the utility of this powerful methodology, an efficient synthesis of γ-secretase inhibitor and the further transformation of the meta-arylphenols are shown. Furthermore, an alternative method is described for the synthesis of meta-arylphenols via a tandem oxidation/arylation/decarboxylation reaction of salicylaldehydes. In Chapter 4, an approach towards the development of enantioselective C-H arylation leading to planar chirality is stated. Preliminary results are presented for this ongoing project.
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Müller, Thomas. "C-H Activation by Nickel and Iron Catalysis." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://hdl.handle.net/21.11130/00-1735-0000-0003-C189-8.
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Gao, Longhui. "C-H bond activation catalyzed by Ruthenium nanoparticles." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS348/document.
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Les molécules marquées par des isotopes de l’hydrogène possèdent de nombreuses applications dans divers domaines tels que la chimie, la biologie ou en science des matériaux. Dans le domaine de la recherche de nouveaux médicaments, les études liées à la pharmacocinétique nécessitent un accès rapide à des molécules marquées afin de ne pas impacter les coûts et les délais de développement. Le développement de la métabolomique a aussi entrainé une augmentation du besoin en molécules marquées isotopiquement. En effet, les molécules deuterées peuvent être utilisées en tant qu’étalons internes pour la quantification rapide des métabolites présents dans des tissus ou des fluides biologiques. La première partie de cette thèse concerne le développement d’une méthode générale de marquage de motifs de type thioéther dans des molécules complexes à l’aide d’une nouvelle réaction d’échange isotopique (catalysée par des nanoparticules de Ruthénium). D’un point de vue fondamental cette transformation représente le premier exemple de (Csp³)-H activation dirigée par un atome de soufre. En termes d’application, cette nouvelle réaction permet la synthèse rapide d’étalons internes pour la quantification LC-MS/MS et le marquage tritium de molécules complexes. La seconde partie de cette thèse relate le développement d’une nouvelle méthode d’homocouplage de phénylpyridines catalysée par Ru/C. Différents substrats comportant des substituants riches et pauvres en électron ont été couplés avec de bons rendements. Ces dimères ont ensuite été utilisés pour synthétiser de nouveaux complexes de bore dont les propriétés photophysiques ont été étudiées. Dans une troisième partie, la mise au point d’une réaction palladocatalysée permettant d’obtenir des molécules polycycliques contenant un motif de type pyridine est développéeDeuterated and tritiated compounds are widely used in numerous applications in chemistry, biology and material science. In the drug discovery and development process, ADME studies require quick access to labelled molecules, otherwise the drug development costs and timeline are significantly impacted. The rapid development of metabolomics has also increased the need for isotopically labelled compounds. In particular, deuterated molecules are used as internal standards for quantitative LC-MS/MS analysis of metabolites in biological fluids and tissues. In this context, a general method allowing the deuterium and tritium labelling of bioactive thioethers using a HIE reaction is described in the first chapter. From a fundamental point of view, this transformation is the first example of (Csp³)-H activation directed by a sulfur atom. In terms of application, this new reaction has been proved to be useful for the preparation of deuterated LC-MS/MS reference materials and tritiated pharmaceuticals owning high specific activity.In the second chapter of this manuscript, the development of a method allowing the cross-dehydrogenative homocoupling of 2-arylpyridines catalyzed by Ru/C is developed. Various substrates with different substituents were efficiently coupled to give the desired dimers in good yield. In terms of application, a series of pyridine-boron complexes derived from the phenyl pyridine dimers were also synthesized and their photophysical properties were studied.In the third chapter, a regioselective palladium catalyzed intramolecular arylation reaction allowing the synthesis of pyridine containing polycyclic compounds is described
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Biswas, Achintesh Narayan. "C-H bond activation by transition metal complexes." Thesis, University of North Bengal, 2010. http://hdl.handle.net/123456789/1362.
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Holstein, Philipp. "Enantioselective C(sp3)-H Arylation and Development of a Modular C(sp3)-H Alkenylation." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10286.
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Récemment, l'activation C-H catalysée par des métaux de transition est devenue un outil performant pour construire des liaisons carbone-carbone et carbone hétéroatome à partir de liaisons C-H omniprésentes dans les molécules organiques. Bien que l'activation des liaisons C-H aromatiques ait été largement étudiée ces dernières années, celle des liaisons C-H aliphatiques représente encore un domaine faiblement exploré. Notre équipe s'est depuis plusieurs années intéressée au développement méthodologique de l'activation C(sp3)-H et à son application en synthèse de produits naturels et molécules bioactives. Dans la continuité des récents travaux sur la version asymétrique de cette réaction, cette thèse décrit le développement et la synthèse de nouveaux ligands du type Binepine. Ces ligands chiraux et monodentates nous ont permis de réaliser la synthèse d'indanes chiraux possédant un centre asymétrique quaternaire, de manière hautement énantio- et diastéréosélective. Cette réaction présente comme avantages l'utilisation d'une faible charge catalytique et d'une température de réaction inférieure à 100 °C, sans aucun additif. Le champ d'application de la réaction inclut notamment l'activation des liaisons C-H d'un groupement méthylène, donnant ainsi accès à des systèmes fusionnés, tricycliques. La construction de molécules non-aromatiques via une alcénylation C-H intramoléculaire a été récemment décrite et s'avère très prometteuse pour la synthèse de produits naturels saturés. Dans la continuité de ces travaux innovants, nous avons développé la synthèse de γ-lactames à partir de bromoalcènes acycliques. Cette nouvelle réaction permet de construire de manière simple et efficace des hétérocycles a cinq chainons de façon modulaire, donnant ainsi la possibilité d'envisager des nouvelles déconnections rétrosynthétiques, complémentaires des méthodes déjà établies. Cette nouvelle méthode a pu être appliquée à la synthèse totale de l'alcaloïde marin Plakoridine A, dont la structure centrale cyclique a été synthétisée en quatre étapes avec un rendement global de 37%Recently, transition-metal-catalyzed C-H activation has emerged as a powerful tool to transform stable C-H bonds into carbon-carbon or carbon-heteroatom bonds. While the activation of aromatic C-H bonds has seen a tremendous development, less effort has been devoted to the more challenging activation of aliphatic C-H bonds. Our group has a long-standing interest in the development of C(sp3)-H activation reactions and their application in the synthesis of natural products and bioactive compounds. In line with previous efforts to develop an asymmetric C(sp3)-H activation, the herein presented work details the synthesis of new Binepine ligands. These monodentate, chiral ligands enabled us to realize a highly dia- and enantioselective C(sp3)-H activation reaction allowing the construction of chiral quaternary carbon centers. Strong points of this robust method are the low catalyst loading, the low reaction temperature and the absence of additives. The substrate scope includes the rare activation of methylene C-H bonds leading to fused tricyclic carbocycles and heterocycles. The construction of non-aromatic molecules through intramolecular C-H alkenylation was recently disclosed and has great potential for the construction of saturated natural products. Based on seminal work, we have developed the synthesis of valuable γ- lactams from acyclic bromoalkenes. This new methodology offers a powerful way to build simple, five-membered N heterocycles in a modular fashion. Notably, it enables a new retrosynthetic disconnection which is complementary to conventional approaches. Finally, we set out to showcase its utility as key step in the total synthesis of the pyrrolidine alkaloid Plakoridine A. The cyclic core structure was accessed in four steps and 37% overall yield
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Schinkel, Marvin. "Rutheniumkatalysierte Addition von nicht aktivierten C(sp²)–H- und C(sp³)–H-Bindungen an Alkene." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://hdl.handle.net/11858/00-1735-0000-0015-A380-B.
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Liu, Weiping. "Ruthenium- and Manganese-Catalyzed C−O and C−C Formation via C−H Activation." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-8771-3.
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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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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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Zhang, Zhuan. "Late Stage Modifications of Phosphines using Transition-Metal-Catalyzed C–H Bond Functionalization." Thesis, Rennes, Ecole nationale supérieure de chimie, 2020. http://www.theses.fr/2020ENCR0067.
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L'objectif principal de cette thèse de doctorat porte sur la préparation de phosphines polyfonctionnelles par diversification tardive de ligands commerciaux. Nous avons développé l'alkylation la liaison C–H en position ortho' des biarylphosphines catalysée par le rhodium(I). Cette nouvelle méthodologie permet d'accéder facilement à une vaste bibliothèque de phosphines multifonctionnelles. Certains de ces ligands modifiés ont surpassé les phosphines disponibles dans le commerce dans la carboxylation des bromures d'aryle catalysée par le palladium avec du dioxyde de carbone en présence d'un catalyseur photoredox. Pour améliorer la diversité des biarylphosphines, nous avons également perfectionné l'alcénylation des liaisons C–H dirigées par l’atome de posphore(III) des (dialkyl)- et (diaryl)biarylphosphines à partir d'alcynes internes. Le [Rh(OAc)(COD)]2 sans chlorure est un meilleur catalyseur que le [RhCl(COD)]2. Les conditions ont été développées pour contrôler la mono- et la difonctionnalisation. Une de ces nouvelles (dialkyl)biarylphosphines bisalcénylées a été utilisée pour la préparation d'un complexe de palladium(II), et certains de ces ligands fonctionnalisés ont surpassé leurs phosphines non fonctionnalisées correspondantes dans l'amidation palladocatalysée de chlorures d'aryle encombrés. Enfin, nous avons également exploré un nouveau protocole pour l'alkylation des liaison C-H de phsophines via la formation des intermédiaires phosphine-ruthénium cyclométallé à 5 ou à 7 chaînons. Ces phosphines fonctionnalisées ont le potentiel d'améliorer les réactions de couplage croisé des (pseudo)halogénures d'aryle encombrésThe main objective of this PhD thesis deals with the preparation of polyfunctional phosphines by late-stage diversification of commercially available ligands. We have developed rhodium(I)-catalyzed ortho’- C–H bond alkylation of biarylphosphines. This new methodology provides a straightforward access to a large library of multifunctionalized phosphines. Some of these modified ligands outperformed commercially available phosphines in the Pd-catalyzed carboxylation of aryl bromides with carbon dioxide in the presence of a photoredox catalyst. To improve the diversity of biarylphosphines, we have also perfected the P(III)-directed C−H bond alkenylation of (dialkyl)- and (diaryl)biarylphosphines using internal alkynes. Chloride-free [Rh(OAc)(COD)]2 acts as a better catalyst than [RhCl(COD)]2. Conditions were developed to control the mono- and difunctionalization. One of these novel bisalkenylated (dialkyl)biarylphosphines was employed for the preparation of a palladium(II) complex, and some of these functionalized ligands outperformed their corresponding unfunctionalized phosphines in Pd-catalyzed amidation of sterically hindered aryl chlorides. Finally, we have also explored a novel protocol C–H bond alkylation of phosphines via 5- or 7- membered ring cyclometallated phosphineruthenium intermediates. These functionalized phosphines have potential to improve crosscoupling reactions of sterically hindered aryl (pseudo)halides
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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.
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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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Ho, Kelvin. "Rapid increase of molecular complexity through C–H and C–C bond activation." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/2006222/.
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The activation of carbon-hydrogen (C–H) and carbon-carbon (C–C) bonds by transition metal catalysts is an attractive strategy to streamline organic synthesis. Herein this manuscript, the two main areas of research are described. Firstly, it was found that a nickel catalyst can promote the insertion of alkynes into the C–C bond of 3-azetidinones and 3-oxetanones to enable quicker access to pyranones and pyridinones in high yields and excellent regioselectivity. Secondly, a rhodium-catalysed pyridine directed C–H bond activation enables the rearrangement of 1,6-heptadienes into bicyclo[2.2.1]heptanes in good yields. Importantly, three stereogenic centres are created with complete diastereocontrol in this atom-efficient reaction. In chapter 1, an overview of the literature on transition metal-catalysed C–C bond activation of four membered rings is described. In chapter 2, our efforts to optimise the catalytic conditions and build the scope of the nickel-catalysed reaction are reported. In chapter 3, the results of the mechanistic investigations of the nickel-catalysed reaction are reported. Finally in chapter 4, a brief overview of the transition metal-catalysed functionalisation of an alkene C–H bond with another alkene is described. Subsequently, the optimisation of the catalytic conditions and the scope of the diastereoselective carbocyclisation of 1,6-heptadienes triggered by rhodium-catalysed activation of an alkene C–H bond are reported.
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Sun, Zhicheng. "Computational Study of C−H/C−C Activation and Functionalization with Nitrene, Carbene and Related Complexes." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1752352/.
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This dissertation involves inorganic/organometallic catalysis models, in particular the functionalization of carbon-hydrogen and carbon-carbon bonds. Computational methods have been utilized to better understand the factors affecting the kinetics and thermodynamics of C−H and C−C bond activation/functionalization in this dissertation. Chapter 2 investigates methane C−H activation with a diiminopyridine nitride/nitridyl complex of 3d transition metals and main group elements via three competing pathways: 1,2-addition/[2 + 2] addition, insertion and H-atom abstraction/proton coupled electron transfer. Chapter 3 investigates a transition metal catalyzed C=C bond functionalization involving C−N bond formations to synthesize aziridines from aromatic and aliphatic alkenes. The study focuses on anionic 3d transition metal (M = Mn, Fe, Co and Ni) triphenylamide-amine complexes with nitrene active intermediates for the aziridination reactions. Chapter 4 investigates a disphenoidal Ni(II) azido complex participating in intramolecular C−H functionalization and amination via a putative Ni nitridyl intermediate and a 1,2-addition/[2 + 2] addition pathway. In Chapter 5, methane oxidative addition to the Cp*ML (Cp* = η5-C5Me5; M = Co, Rh, Ir , L = CO, PMe3) motif is compared and contrasted when the classic CO and PMe3 ligands are replaced with the cyclic alkyl(amino) carbene (CAAC) as ancillary ligands.
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Thongpaen, Jompol. "Ligands NHCs bifonctionnels en fonctionnalisation C-H métallo-catalysée." Thesis, Rennes, Ecole nationale supérieure de chimie, 2019. https://www.ensc-rennes.fr/formations/doctorats.
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La fonctionnalisation directe des liaisons Carbone-hydrogène (C-H) a pris, au cours des deux dernières décennies, une place de plus en plus importante en synthèse organique. En particulier, la fonctionnalisation CH catalysée par un métal de transition (TM) a connu une amélioration croissante de ses performances, permettant ainsi d'élargir la palette d'outils disponibles pour la synthèse de matériaux organiques, de produits naturels et de principes actifs. Néanmoins, le développement de nouvelles transformations de liaisons C-H fonctionnant efficacement en conditions douces avec une large tolérance aux groupements fonctionnels et une sélectivité élevée reste un enjeu majeur. Parallèlement, les carbènes N-hétérocycliques (NHCs) sont devenus des ligands de choix en chimie de coordination et en catalyse. Leurs propriétés uniques sont a l’origine de catalyseurs robustes de métaux de transition permettant des stratégies de synthèse plus efficaces. Cependant, l'utilisation des ligands NHCs dans des procédés métallo-catalysés de fonctionnalisation C-H reste a ce jour limitée. Par ailleurs, les composes organoborés sont des intermédiaires polyvalents en chimie de synthèse. Les stratégies mettant en jeu la fonctionnalisation C-H représentent sans nul doute l’approche la plus simple pour accéder a ces blocs de synthèse. Cette Thèse décrit une stratégie efficace et simple pour la préparation de complexes de métaux de transition portant des ligands chélates de type NHC-carboxylate sans précédent dans la littérature. Ces complexes, présentent une efficacité et une sélectivité élevée en tant que catalyseurs dans des réactions de borylation regiosélective de liaisons C-H dites ≪ inertes ≫ en conditions douces, et notamment photochimiquesThe direct functionalization of inert CH bonds has emerged over the past two decades as an increasingly important synthetic tool. In particular, transition metal (TM)-catalyzed C-H functionalization has witnessed continuing improvements in performance, allowing expansion of the toolbox available for organic material synthesis, natural products synthesis, and drug-discovery programs. In spite of this success, there is still a need for the development of methodologies to efficiently enable C-H bond transformation under mild conditions. During the past two decades, N-heterocyclic carbenes (NHCs) have become ubiquitous ligands in coordination chemistry and catalysis. Their unique properties, including strong σ- donation, are responsible for forming robust TM catalysts that allow for the development of more efficient synthetic procedures. Nevertheless, the use of NHC ligands in transition metal-catalyzed C-H functionalization has remained limited. Because organoboron compounds are versatile intermediates in synthetic chemistry, the development of new catalytic systems for selective borylation of unactivated C-H bonds would afford new perspectives in organometallic and catalysis. Herein, this Thesis discloses an efficient and straightforward strategy to access various types of transition metal complexes bearing bidentate NHC-carboxylate ligands which were fully characterized including solid-state structures. These unprecedented complexes possessing chelating-NHC ligands exhibited high efficiency and selectivity in site selective borylation of inert C-H bonds under mild conditions including a photosensitizer-free photocatalytic conditions
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Macdonald, Margaret G. Templeton J. L. "Hydrocarbon C-H activation with Tp[prime]Pt complexes." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,788.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2007.Title from electronic title page (viewed Dec. 18, 2007). " ... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry." Discipline: Chemistry; Department/School: Chemistry. On t.p., [prime] is the mathematical symbol.
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Boutadla, Youcef. "Acetate-assisted C-H activation : mechanism, scope and applications." Thesis, University of Leicester, 2010. http://hdl.handle.net/2381/8592.
Full textAbstract:
This thesis describes mechanistic investigations of acetate assisted C-H activation, the synthesis of cyclometallated complexes containing nitrogen donor ligands via this method and the applications of cyclometallated complexes in terms of insertion reactions. Chapter one introduces the synthesis, by C-H activation, of cyclometallated complexes containing C,N bidentate ligands of palladium, ruthenium, rhodium and iridium. The introduction also gives an overview on the mechanisms of C-H activation and the applications of C-H activation in catalysis, particularly in direct arylation. Chapter two provides an introduction to the synthesis of arene ruthenium and Cp*M (M = Ir, Rh) half sandwich cyclometallated complexes). The scope of cyclometallation via acetate- assisted C-H activation with different directing groups (pyrazole, pyridine, imines, imidazole, oxazoline and triazole) is discussed. The methodology is extended to six membered rings, non aromatic sp2 and sp3 C-H bonds. Mechanistic investigations using bidentate ligands showed that chelating ligands can prevent the C-H activation process. Chapter three describes a joint computational and experimental study of the cyclometallation reactions of dimethylbenzylamine (DMBA) with [IrC12Cp*]2 using a range of chelating bases. DFT calculations show that facile C-H bond cleavage occurs via 'ambiphilic metal ligand activation' (AMLA) and the ease of C-H activation is governed by the accessibility of the K2-xl base displacement step; thus, more weakly coordinating bases promote C-H activation. Chapter four reports the reactivity of cyclometallated half-sandwich complexes (synthesised in chapter two). Alkynes are shown to insert into the M-C bond. In some cases C-N bond formation occurs to form a heterocycle. The product formed depends on the ease of the reductive elimination step. The relevance of these results to the catalytic synthesis of hetero-and carbocycles is discussed. Throughout the thesis all new compounds are fully characterised spectroscopically and by elemental analysis and several compounds have been structurally characterised by X-ray crystallography.
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Ravetz, Megan Sarah. "Effect metal electron density on C-H activation reactions." Thesis, University of Salford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360458.
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Fowles, E. H. "Transition metal multihydrides and aspects of C-H activation." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233726.
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Fan, Cheng. "Dichloroboryls, diboration and C-H activation with platinum complexes." Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443267.
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