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1

Saari, N. (Niko). "Mono- ja regioselektiivisyys Suzuki-Miyaura -ristiinkytkennöissä." Master's thesis, University of Oulu, 2016. http://urn.fi/URN:NBN:fi:oulu-201606032212.

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Suzuki–Miyaura -ristiinkytkentä on yksi tänä päivänä eniten käytetyistä menetelmistä, joilla muodostaa uusia C–C -sidoksia eri yhdisteiden välille. Menetelmää käytetään paljon varsinkin hienokemikaalien ja lääkeaineiden valmistuksessa. Reaktion etuina ovat sivutuotteiden helppo poistettavuus sekä reaktion toimintavarmuus, vaikka reaktiossa olisi läsnä useita erilaisia funktionaalisia ryhmiä. Reaktiossa halogenoitu aryyli-/allyyliryhmä ja boorihappo-/boorihappoesteriryhmän sisältävä aryyli-/allyyliryhmä kytkeytyvät toisiinsa Pd-avusteisessa katalyyttisessa syklissä. Syklissä booriryhmä muodostaa suolan halogeenin kanssa ja syntyy uusi sidos orgaanisten ryhmien välille. Lisätty emäs sekä Pd:iin liittyvät ligandit ovat erittäin tärkeitä tekijöitä reaktion toiminnan kannalta. Menetelmää on tutkittu paljon, mutta reaktioiden mono- ja regioselektiivisyyttä ei pystytä vielä ennustamaan varmasti. Kytkennän paikka tiedetään, jos reaktiossa käytetään monohalogenoitua yhdistettä sekä boorihapporeagenssia. Tilanne kuitenkin vaikeutuu merkittävästi, jos reaktiossa käytetään polyhalogenoitua lähtöainetta. Tällaisessa tilanteessa selektiivisyyttä on lähes mahdoton ennustaa ilman kokeellisia tutkimuksia. Tässä pro gradu -tutkielmassa on selvitetty eri tekijöitä jotka vaikuttavat dihalogenoitujen yhdisteiden mono- ja regioselektiivisyyteen. Tämän lisäksi tutkielmassa käsitellään useita reaktioita, joissa mono- tai regioselektiivisyys on saavutettu reaktio-olosuhteita muuttamalla tai käyttämällä ohjaavia ryhmiä. Tutkielmassa käydään läpi myös reaktioita, joissa regioselektiivisyys on saavutettu molempiin halogenoituihin hiiliin muuttamalla reaktio-olosuhteita. Näiden reaktioiden pohjalta on esitetty tärkeimmät tekijät, joiden avulla kytkentöjen selektiivisyyttä voitaisiin mahdollisesti pystyä ohjaamaan haluttuun paikkaan.
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2

Hashimoto, Toru. "Development of Iron-Catalyzed Suzuki-Miyaura Coupling Reaction." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/159407.

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3

Geogheghan, Katherine Jayne. "Boronic acid speciation in Suzuki-Miyaura cross-coupling." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33092.

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Since its discovery in 1979, the Suzuki-Miyaura (SM) reaction has become one of the most widely utilised tools for carbon-carbon bond formation. The palladium catalysed coupling of an organoboron and organohalide compounds proceeds through a three-stage mechanism of oxidative addition, transmetalation and reductive elimination. The transmetalation of boronic acids to a palladium(II) complex has been widely studied. However, very little is known about the transmetalation of boronic esters, which are commonly used as an alternative to unstable boronic acids. Whether these species undergo direct transmetalation or prior hydrolysis to the boronic acid under SM conditions remains unknown. This research aimed to elucidate the mechanism of this cross-coupling process. Initial results under typical SM conditions created a biphasic reaction, promoted by the inorganic base and solvent composition, and showed that the boronic esters and corresponding boronic acid couple at the same absolute rate. This is thought to be a consequence of the formation of a biphasic mixture, rendering phase transfer the turnover-limiting step. The conditions were thus adapted to maintain a monophasic system using an organic soluble base, 2-tert-butyl-1,1,3,3-tetramethylguanidine, enabling the focus to be transmetalation as the turnover-limiting step. These new conditions show a significant difference in both reaction rate and induction period when using a boronic ester compared to the corresponding boronic acid. The use of guanidine was also shown to have an interesting effect on the boronic acid/ester species by 19F and 11B NMR. Further studies found the use of guanidine to create a boronate species, with this species being an aryl trihydroxyboronate or the hydroxyl"ate"-complex of the boronic ester, depending on the presence of diol in the system. Formation of a boronate species was found to be crucial for efficient cross-coupling. When testing weaker bases, unable to form a boronate species, poor SM cross-coupling conversion was found using the newly developed phosphine-free guanidine conditions, showing the importance of the boronate species under these conditions. The results suggest that depending on the strength of base used, the pathway of transmetalation pathway can be switched, between the boronate pathway and the oxo-palladium pathway, under the specific conditions developed.
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4

Le, Duc Gaëtan. "Etude mécanistique de la réaction de Suzuki-Miyaura." Paris 6, 2011. http://www.theses.fr/2011PA066333.

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La réaction de couplage croisé de Suzuki-Miyaura, catalysée par le palladium(0), entre un halogénure aromatique et un acide arylboronique, est l’une des réactions les plus utilisées pour la synthèse de biaryles. La particularité de cette réaction est qu’elle nécessite la présence d’une base. Le rôle de la base n’est pas bien défini dans la littérature où plusieurs hypothèses sont proposés, dans lesquelles la base jouerait un rôle dans l'étape de transmétallation. Nous avons étudié le rôle de la base (hydroxydes, carbonates, fluorures) dans l’étape de transmétallation grâce à des méthodes électrochimiques et spectroscopiques. Nous nous sommes également intéressés aux effets induits par les contre cations. Nous avons alors mis en évidence un quadruple rôle de la base. Elle¨permet la formation des complexes trans-ArPd(OH)(PPh3)2 (ou trans-ArPdF(PPh3)2) qui réagissent avec l'acide arylboronique et celle des ions arylborates à partir de l'acide arylboronique. Cet ion arylborate est non réactif vis-à-vis des complexes de palladium(II). Comme sa formation se fait au détriment d’une espèce active, ce deuxième effet de la base ralentit la réaction. La base est donc responsable de deux effets antagonistes dans l’étape de transmétallation. La base joue également un rôle accélérateur dans l’étape d’élimination réductrice, en favorisant la formation du complexe de Pd(0) et du produit de couplage. Le contre cation ralentit la réaction de transmétallation par complexation au ligand hydroxo des complexes trans-ArPd(OH)(PPh3)2. L’ensemble de nos résultats nous a permis d’élucider le mécanisme de la réaction de Suzuki-Miyaura
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5

Fyfe, James William Buchanan. "Chemoselective Suzuki-Miyaura cross-coupling enabled by speciation control." Thesis, University of Strathclyde, 2017. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27909.

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Boronic acids and esters are one of the most widely used compound classes inorganic chemistry. Recently, diboron systems have emerged as a powerful approach towards complex molecule synthesis. Selectivity in these systems is typically achieved through the use of protecting group strategies in which one boron residue is rendered unreactive under the prevailing reaction conditions, allowing selective manipulation of an unprotected unit. However, while these methods offer excellent selectivity, they do have the drawback of requiring additional synthetic manipulations, i.e., removal of the protecting group to allow subsequent functionalisation, limiting the overall efficiency of these processes. Boronic acids and esters undergo complex equilibria in solution. We have shown that control of these equilibria has been leveraged during the Suzuki-Miyaura reaction to enable the formation of a new, reactive BP in ester without the need for additional protecting group manipulations. Extensive optimisation identified that the nature of the base and quantity of water in the reaction were key in controlling the speciation events in the reaction. This allowed the generation of a broad substrate scope of formally homologated BPin esters. These newly generated reactive boron species were then reacted in situ in an iterative process, forming either terminal triaryl or contolled homologation products. The reaction was also found to have a temperature dependence, where under identical controlled basic conditions either the homologated BPin or the cross-coupled BMIDA species could be obtained based purely upon the temperature of the reaction. A series of control reactions aided in identifying the key processes in the reaction and, more importantly, the order in which these processes must occur in order to achieve the desired reaction. This work led to the development of methods to enable chemoselective reactions within non-protected diboron systems. This demonstrated how chemoselective Suzuki-Miyaura cross-coupling can be achieved within boronic acid/BPin esterdiboron systems by exploiting kinetic control of transmetallation while maintaining control of solution speciation events. This allows the selective reaction of boronic acids in the presence of BPin esters again without the need for protecting group manipulations, as either additional synthetic steps or in situ. Chemoselective transmetallation was then combined with chemoselective oxidative addition in order to establish the first complete chemoselective control over two of the three key mechanistic processes of the Suzuki-Miyaura reaction. This enables a one-pot sequential chemoselective Suzuki-Miyaura reaction without the requirement for any in situ modification of the reaction conditions (temperature change, sequential addition) or reactants (protecting group removal, boron species interconversion).
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6

Andert, William D. "Palladium Catalyzed Suzuki-Miyaura Cross-Coupling of Axially Chiral Biaryls." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1367536419.

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7

Horhant, David. "Borylation pallado-catalysée et couplages de Suzuki-Miyaura boro-sélectifs." Rennes 1, 2005. http://www.theses.fr/2005REN1S079.

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Ce mémoire traite de l'utilisation d'une réaction pallado-catalysée de borylation pour l'obtention d'organoboranes et leur implication dans la synthèse de molécules à haute valeur ajoutée ou d'intérêt synthétique. Cette réaction utilise un pourvoyeur de bore original, le (N,N-diisopropylamino)borane, dérivé de la famille des aminoboranes monomères. Dans un premier temps, la synthèse d'amino-oxazoles, précurseurs de biarylcyclopeptides, a été réalisée via une réaction multi-composants entre un aldéhyde à terminaison acide arylboronique et divers isocyanoacétamides. Les biaryles sont obtenus par macrocyclisation décrochante sur support solide ionique. Ensuite, la synthèse de triazènes arylboroniques, des molécules difonctionnelles polyvalentes, a été réalisé. Ces outils synthétiques ont été engagés avec succès dans des réactions de Suzuki-Miyaura, et plus particulièrement dans des couplages originaux boro-sélectifs. L'utilisation de ces triazènes boroniques a également permis de réaliser la synthèse de molécules complexes de type DiSpiro[Fluorène-Indénofluorène-Fluorène] (DSFIFs), précurseurs de matériaux conducteurs et luminescents.
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8

Bourouina, Amine. "Desperately Seeking For The Catalytic Species In Suzuki-Miyaura Reaction." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1258.

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L’état de l’art montre que l’utilisation de Pd supporté sans ligand est une idée séduisante car elle permet d’éviter les problèmes liés à la présence des ligands potentiellement coûteux et toxiques, et également de récupérer plus facilement le catalyseur en fin de réaction. Ainsi, il est plus aisé de respecter la réglementation fixant la teneur maximale de Pd dans les principes actifs pharmaceutiques (IPA) à une concentration inférieure à 10 ppm. Cependant, la présence des espèces (moléculaires ou nanoparticules) de Pd en solution lors de l’utilisation de catalyseurs solides a créé un débat important dans la bibliographie sur la vraie nature de la catalyse, hétérogène à la surface du Pd supporté ou homogène par l’intermédiaire d'espèces en solution. Dans ce travail la réaction de Suzuki-Miyaura (SM) a été choisie comme réaction cible. En absence d’étude cinétique globale dans la bibliographie une étude cinétique a été effectuée avec un catalyseur moléculaire afin d’obtenir une loi mécanistique qui représente la partie homogène de la réaction. Un test innovant a été proposé afin de bien distinguer entre les contributions homogène et hétérogène et de déterminer par la suite la nature des espèces qui catalysent la réaction. Ce test a été appliqué dans la réaction de différents iodo, bromo, et chloro aryles en utilisant plusieurs catalyseurs supportés tout en variant la nature du support et l’état d’oxydation du Pd (Pd(0) et Pd(II)) dans le précurseur initial. Enfin, un modèle de réacteur a permis de démontrer que pour le même iodoaryle, peu importe la nature du solide, le Pd supporté semble relarguer les mêmes espèces actives en solution qui catalysent la réaction SM avec des activités initiales de l’ordre de 500 000 h-1. Le « split flow reactor » est un nouveau test très simple à utiliser qui, accompagné de techniques d’analyses en ligne, peut permettre de suivre l’évolution des espèces catalytiques en temps réel, et d’étudier d’autres systèmes chimiques
The use of ligand-free supported Pd is an attractive idea because it avoids problems related to the presence of the ligands (cost and toxicity). Also the catalyst is easily recovered at the end of the reaction by conventional methods such as filtration or decantation. Thus, it is easier to meet regulations in Active Pharmaceutical Ingredients (<10 ppm). However, the presence of molecular or atomic Pd species in solution when using solid catalysts has created an important discussion on the true nature of catalysis. This last could be heterogeneous on the surface of the supported Pd or homogeneous via species in solution. In this work the Suzuki-Miyaura (SM) reaction was chosen as the target reaction. In the absence of an overall kinetic study in the literature, a kinetic study was carried out with a molecular catalyst. It provided a mechanistic law that represents the homogeneous part of the reaction. Furthermore, an innovative test (“split flow reactor”) has been proposed. It permits to distinguish between the homogeneous and heterogeneous contributions and to determine the nature of the species that catalyze the reaction. It was used in the reaction of different iodo, bromo, and chloro aryls. Several supported catalysts were used by varying the nature of the support and the oxidation state of Pd (Pd (0) and Pd (II)) in the initial precursor. Finally, a reactor model has shown that for the same iodoaryl, whatever the nature of the solid, the supported Pd seems to release the same active species in solution. These species catalyze the SM reaction with initial activities of the order of 500 000 h-1. The split flow reactor is a new, easy-to-use test. Accompanied with online analysis techniques, it can be used to track the evolution of catalytic species in real time and to study other chemical systems
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9

Requet, Alexandre. "Une catalyse vertueuse menant à des architectures moléculaires complexes." Thesis, Versailles-St Quentin en Yvelines, 2014. http://www.theses.fr/2014VERS0047/document.

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Les travaux de recherche s'articulent autour de l'élaboration de nouveaux ligands à plateformepyridylméthylamine, de l'étude de leur activité catalytique, et de leur application potentiellepour la construction d'édifices hélicéniques. La première partie consiste en la synthèse denouveaux ligands pma. Un travail méthodologique a été effectué afin de trouver le meilleurcompromis entre un nombre d'étapes limitées, des conditions douces, un apport de chiralité etune possibilité d'apporter une importante diversité structurale. La deuxième partie de cemanuscrit concerne l'étude catalytique des ligands synthétisés dans diverses transformationscomme le couplage de Suzuki-Miyaura, le couplage oxydant au cuivre et l'additionnucléophile par un organozincique. Les premiers éléments d'une étude structure activité desligands pma appliqués aux couplages de Suzuki-Miyaura a été réalisée en solution grâce à laRMN 15N. La dernière partie repose sur la construction d'architectures moléculairescomplexes et la possibilité de gérer la chiralité axiale dans l'étape clé de leur synthèse
The manuscript is dealing with the development of new ligands pyridylmethylamine platformfor the study of their catalytic activity and potential application for the construction of helicalarchitectures. The first part describes the synthesis of new pma ligands. Attention has beenpaid to define the best compromise between a limited number of steps, mild conditions,introduction of chirality at key steps and opportunities to reach structural diversity. Thesecond part concerns the catalytic study of these ligands in various transformations such as Pdcatalysis in Suzuki-Miyaura coupling, Cu catalysis in oxidative coupling copper and Znpromoted nucleophilic addition. First lines of structure-activity relationships has been realizedusing 15N. Finally the last part is devoted to the construction of helical moleculararchitectures. Axial chirality is installed in key coupling step
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10

Baltus, Christine B. "Suzuki-Miyaura mediated biphenyl synthesis : a spotlight on the boronate coupling partner." Thesis, University of Greenwich, 2011. http://gala.gre.ac.uk/8038/.

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The biaryl motif is found in many natural and synthetic products that display a wide range of biological activities. This explains why biphenyls are widely encountered in medicinal chemistry as a privileged scaffold. The palladium-catalysed Suzuki-Miyaura (SM) coupling is one of the most important and efficient strategies for the synthesis of symmetrical and unsymmetrical biaryl compounds; the arylboronic acid or ester is a key partner in this coupling reaction. This work presents the synthesis of a library of new molecules containing the biphenyl scaffold; o-, m- and p-(bromomethyl)phenylboronic acid pinacol esters, 2a-c, were selected as coupling partners. Nucleophilic substitution of the bromide was carried out with amine, thiol, alcohol or phenol nucleophiles. Supported reagents and microwave assisted organic synthesis conditions were employed to enhance this chemistry and made it amenable to parallel synthesis. The resulting arylboronates were used in SM coupling reactions in order to obtain a range of biphenyls. The use of Boc-piperazine as a nucleophile in the SN2 reaction, with 2a-c, and 1-bromo-, 2-, 3- or 4-nitrobenzene or 2-bromo-5-nitropyridine as aryl halides in the SM coupling reaction, allowed two other points of functionalisation to be added to the biaryl motif. The conditions for the SM coupling of mercaptomethylphenylboronic esters and orthosubstituted methylphenylboronic esters were optimised in order to broaden the scope of the biaryl library. Phosphines were found to be good nucleophiles in the SN2 reaction with 2a-c. A Wittig reaction was performed with the resulting phosphonium arylboronates in order to synthesise arylboronic esters containing an alkene function prior the reduction of the resulting double bond of the stilbene derivatives and realising a SM coupling to synthesise arylethylbiphenyls. The stilbene derivatives were also synthesised by using the olefin cross-metathesis reaction of 4-vinylphenylboronic acid pinacol ester. A solid state crystallographic study was undertaken on a small library of methylbiphenylamides to compare the crystal structures of isomers or biphenyls with different functional groups.
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11

Karabiyikoglu, Sedef. "Synthesis Of Ferrocenyl Substituted Pyrazoles By Sonogashira And Suzuki-miyaura Cross-coupling Reactions." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12612139/index.pdf.

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Pyrazoles constitute one of the most important classes of heterocyclic compounds due to their interesting chemical and biochemical features. Researchers have studied many pyrazole containing structures for almost over a century in order to investigate the various biological activities possessed by these molecules. A new and important trend in these studies is to produce ferrocenyl substituted pyrazoles since ferrocene attracts considerable interest in the research field of organometallic and bioorganometallic chemistry because of its valuable chemical characteristics like high stability, low toxicity and enhanced redox properties. Moreover, the results of the studies focusing on ferrocenyl compounds have been quite promising. Therefore, the scope of this project involves the combination of the essential structural features of pyrazoles with a ferrocene moiety, which could provide new derivatives with enhanced biological activities. In the course of the project the synthesis of new pyrazole derivatives was performed through Sonogashira and Suzuki-Miyaura cross-coupling reactions of 5-ferrocenyl-4-iodo-1-phenyl-1H-pyrazole with terminal alkynes and boronic acids respectively in the presence of a catalytic amount of PdCl2(PPh3)2. Although Sonogashira and Suzuki-Miyaura coupling reactions are well known in literature, they were not studied in much detail with multi-substituted pyrazoles. This also revealed the requirement of the reinvestigation of the reactions and improvement of the yields of pyrazoles by optimizing the reaction conditions.
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12

Bonin-Dubarle, Hélène. "Variations autour de la réaction de Suzuki-Miyaura : nouveaux partenaires et nouveaux ligands." Toulouse 3, 2009. http://thesesups.ups-tlse.fr/1545/.

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"Les réactions de couplage carbone-carbone sont des réactions essentielles en chimie organique. Parmi les différentes approches métallo-catalysées, la réaction de Suzuki-Miyaura est celle qui a connu un développement industriel et académique parmi les plus importants, car elle présente de nombreux avantages par rapport aux autres réactions de couplage existantes. Cependant, les acides boroniques utilisés classiquement dans cette réaction présentent des problèmes de stabilité. C'est pourquoi d'autres partenaires de couplage ont été élaborés et utilisés avec succès à la place de ces acides. Parmi les différents partenaires mis au point, les dioxazaborocanes, obtenus par condensation de la diéthanolamine sur un acide boronique, se sont avérés être d'excellents alternatifs aux acides boroniques, notamment grâce à leur purification très simple à mettre en œuvre, et à leur exceptionnelle stabilité. Dans le cadre d'une collaboration avec un partenaire industriel, nous nous sommes intéressés à la synthèse " one-pot " et à la structure de ces composés, aussi bien en série alkyle qu'en série aryle. Nous avons alors mis au point des conditions de couplage de ces différents composés, aussi bien sur des dérivés halogénés que sur des sels de diazonium, et permettant d'obtenir d'excellents rendements de réaction. En plus du développement de nouveaux partenaires borés, nous nous sommes également intéressés à la synthèse de nouveaux ligands et des complexes de palladium correspondants pour catalyser la réaction de Suzuki-Miyaura. Afin d'obtenir des complexes organométalliques extrêmement robustes, nous avons choisi de développer des ligands bidentates comportant un motif carbène N-hétérocyclique et un motif triazole relié entre eux par un bras méthylène, notamment grâce à la réaction de Huisgen. Les complexes mixtes carbène-phosphine correspondants ont alors pu être obtenus avec de bons rendements. Les tests catalytiques, effectués avec deux complexes de palladium sur la réaction de Suzuki-Miyaura, ont été très concluants, puisque ces catalyseurs permettent d'obtenir des rendements de couplage quantitatifs avec des temps de réaction très courts et des charges catalytiques très faibles. "
Carbon-carbon bond formation is a fundamental reaction in organic chemistry. Among the different transition-metal catalysed cross-coupling reactions, the Suzuki-Miyaura reaction is known as one of the most efficient and popular method in academic laboratories and at an industrial level. However, the classically used boronic acids are not very stable. That's why new boronated coupling partners have been developed and successfully used in this type of reaction. Among these new compounds, dioxazaborocanes, obtained by condensation of diethanolamine on boronic acids, are a very good choice, because of their simple purification and their exceptional stability. We developed with our industrial partner a new one-pot synthesis of these derivatives, and then, studied their structure in solution and in a solid state. We also tested different catalytic conditions to obtain the cross-coupling products with excellent yields from halogenated compounds or diazonium salts. We were also interested in developing new ligands and the corresponding palladium complexes to catalyse the Suzuki-Miyaura reaction. In order to get very strong ligand-metal complexes, we chose to develop bidentate ligands, containing an N-heterocyclic carbene and a triazole ring linked by a methylene, by using the Huisgen reaction. The corresponding palladium complexes were then synthesized with good yields. These complexes are excellent catalysts, since we could obtain cross-coupling products in quantitative yields with very low catalyst loading and in very short reaction times
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13

Fischer, Christoph Siegfried Winfried [Verfasser]. "Luminescent Conjugated Polymer Nanoparticles from Suzuki-Miyaura Chain-Growth Polymerization / Christoph Siegfried Winfried Fischer." Konstanz : Bibliothek der Universität Konstanz, 2015. http://d-nb.info/1105479110/34.

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14

Riemer, Martin. "Vom Phenol zum Naturstoff : Entwicklung nachhaltiger Mikrowellen-vermittelter SUZUKI-MIYAURA-Kupplungen und Tandem-Reaktionen." Phd thesis, Universität Potsdam, 2014. http://opus.kobv.de/ubp/texte_eingeschraenkt_verlag/2015/7252/.

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Ziel dieser Arbeit war die Entwicklung von Methoden zur Synthese von auf Phenol basierenden Naturstoffen. Insbesondere wurde bei der Methodenentwicklung die Nachhaltigkeit in den Vordergrund gerückt. Dies bedeutet, dass durch die Zusammenfassung mehrerer Syntheseschritte zu einem (Tandem-Reaktion) beispielsweise unnötige Reaktionsschritte vermieden werden sollten. Ferner sollten im Sinne der Nachhaltigkeit möglichst ungiftige Reagenzien und Lösungmittel verwendet werden, ebenso wie mehrfach wiederverwertbare Katalysatoren zum Einsatz kommen. Im Rahmen dieser Arbeit wurden Methoden zum Aufbau von Biphenolen mittels Pd/C-katalysierten Suzuki-Miyaura-Kupplungen entwickelt. Diese Methoden sind insofern äuÿerst ezient, da der ansonsten gebräuchliche Syntheseweg über drei Reaktionsschritte somit auf lediglich eine Reaktionsstufe reduziert wurde. Weiterhin wurden die Reaktionsbedingungen so gestaltet, dass einfaches Wasser als vollkommen ungiftiges Lösungsmittel verwendet werden konnte. Des Weiteren wurde für diese Reaktionen ein Katalysator gewählt, der einfach durch Filtration vom Reaktionsgemisch abgetrennt und für weitere Reaktionen mehrfach wiederverwendet werden konnte. Darüber hinaus konnte durch die Synthese von mehr als 100 Verbindungen die breite Anwendbarkeit der Methoden aufgezeigt werden. Mit den entwickelten Methoden konnten 14 Naturstoffe - z. T. erstmals - synthetisiert werden. Derartige Stoffe werden u. a. von den ökonomisch bedeutenden Kernobstgewächsen (Äpfeln, Birnen) als Abwehrmittel gegenüber Schädlingen erzeugt. Folglich konnte mit Hilfe dieser Methoden ein Syntheseweg für potentielle Pflanzenschutzmittel entwickelt werden. Im zweiten Teil dieser Arbeit wurde ein Zugang zu den sich ebenfalls vom Phenol ableitenden Chromanonen, Chromonen und Cumarinen untersucht. Bei diesen Untersuchungen konnte durch die Entwicklung zweier neuer Tandem-Reaktionen ein nachhaltiger und stufenökonomischer Syntheseweg zur Darstellung substituierter Benzo(dihydro)pyrone aufgezeigt werden. Durch die erstmalige Kombination der Claisen-Umlagerung mit einer Oxa-Michael-Addition bzw. konjugierten-Addition wurden zwei vollkommen atomökonomische Reaktionen miteinander verknüpft und somit eine überaus effiente Synthese von allyl- bzw. prenylsubstituierten Chromanonen und Chromonen ermöglicht. Ferner konnten durch die Anwendung einer Claisen-Umlagerung-Wittig-Laktonisierungs-Reaktion allyl- bzw. prenylsubstituierte Cumarine erhalten werden. Herausragendes Merkmal dieser Methoden war, dass in nur einem Schritt der jeweilige Naturstoffgrundkörper aufgebaut und eine lipophile Seitenkette generiert werden konnte. Die Entwicklung dieser Methoden ist von hohem pharmazeutischem Stellenwert, da auf diesen Wegen Verbindungen synthetisiert werden können, die zum einem über das notwendige pharmakologische Grundgerüst verfügen und zum anderen über eine Seitenkette, welche die Aufnahmefähigkeit und damit die Wirksamkeit im Organismus beträchtlich erhöht. Insgesamt konnten mittels der entwickelten Methoden 15 Chromanon-, Chromon- und Cumarin-Naturstoffe z. T. erstmals synthetisiert werden.
The aim of this work was the development of methods for the synthesis of natural products based on phenol. In particular, in developing methods, sustainability has been brought to the fore. This means that, for example, unnecessary reaction steps should be avoided by the combination of several synthetic steps to a (tandem reaction). Furthermore, non-toxic as possible in terms of sustainability reagents and solvents should be used, as well as multiple reusable catalysts are used. In this work, methods have been developed for the synthesis of bisphenols using Pd / C-catalyzed Suzuki-Miyaura coupling reactions. These methods are so far äuÿerst e? Cient, since the otherwise common synthetic route was thus reduced to merely a reaction stage, three reaction steps. Furthermore, the reaction conditions were designed to plain water could be used as a completely non-toxic solvent. It was also elected a catalyst for these reactions, which could be easily separated by filtration from the reaction mixture and reused several times for further reactions. In addition, it could be demonstrated through the synthesis of more than 100 compounds, the broad applicability of the methods. ., For the first time T. - - Using the methods developed 14 natural compounds could be synthesized. Such substances are among others generated by the economically important pome fruit crops (apples, pears) as a defense against pests. Consequently, it could be developed using these methods, a synthetic route for potential plant protection products. In the second part of this work, access to the likewise derived from phenol chromanones, chromones and coumarins was investigated. In these studies, a sustainable and economical route in stages to represent substituted benzo (dihydro) pyrones could be demonstrated by the development of two new tandem reactions. The initial combination of the Claisen rearrangement with an oxa-Michael addition or conjugated addition of two perfectly atom-economical reactions were interlinked and thus allows a very effiente synthesis of allyl or prenylsubstituierten chromanones and chromones. Furthermore or prenylsubstituierte coumarins could be obtained by the application of a Claisen rearrangement Wittig lactonization reaction allyl. The outstanding feature of these methods was that built up in only one step of the respective natural product base and a lipophilic side chain could be generated. The development of these methods is of great pharmaceutical importance, since these paths compounds can be synthesized on a the necessary pharmacological Backbone and on the other hand have a side chain, which increases the absorption and thus the effectiveness in the body considerably. Overall, z. T. were synthesized using the methods developed Chromanon- 15, chromone and coumarin-natural products for the first time.
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15

TICHKOWSKY, ISABELLE. "Syntheses totales de la monocilline et du radicicol via des couplages de miyaura-suzuki." Paris 6, 1996. http://www.theses.fr/1996PA066412.

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Ce travail decrit une nouvelle voie d'acces a la monocilline et au radicicol (monordene), macrolides resorcyliques possedant de nombreuses proprietes pharmacologiques (activites fongistatiques, inhibition specifique de la tyrosine kinase p60src, inhibition specifique de l'expression de la cyclooxygenase 2). Des couplages de miyaura-suzuki entre une isocoumarine halogenee en position allylique et des dialkylvinylboranes ou vinylboronates, catalyses par des complexes du palladium, permettent d'acceder avec de bons rendements aux precurseurs du macrolide. Les vinylboranes et boronates sont obtenus par hydroboration des alcynes correspondants par le disiamylborane ou le dicyclohexylborane (suivie d'une oxydation dans le cas des vinylboronates) et ceci sans toucher a l'epoxyde. Les organoboranes etant relativement sensibles aux traces d'oxygene, les couplages sont realises en un pot. L'influence de nombreux parametres (nature de la base, du solvant, du catalyseur, du boronate) a ete etudiee et commentee afin de mieux preciser certains points du mecanisme de la reaction de couplage (role de la base, nature de l'entite catalytique, nature de l'etape limitante). Des conditions relativement douces (phosphate de potassium, carbonate de sodium), associees a une catalyse par le palladium zero, permettent de preserver les structures pendant le couplage, celles-ci etant tres sensibles aux nucleophiles et aux bases. L'amelioration de certaines etapes (clivage de l'isocoumarine, generation du systeme dienone epoxyde conjugue), la flexibilite et la convergence de cette synthese donnent un acces stereospecifique a des macrolides homochiraux apparentes a la monocilline et au radicicol et non isoles de sources naturelles
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16

Silva, Maurício Chagas da. "Estudo teórico de efeitos de solvatação do tetraidrofurano sobre um mecanismo modelo de Suzuki-Miyaura." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248953.

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Orientador: Nelson Henrique Morgon
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Utilizando a implementação do método da coordenada geradora discretizada nos orbitais atômicos, conjuntos de bases adaptados ao pseudopotencial de caroço SBKJC (conjuntos GBSMCS) foram desenvolvidos, validados e utilizados no estudo de possíveis efeitos de solvatação do tetraidrofurano sobre um mecanismo modelo de Suzuki-Miyaura. As metodologias de validação adotadas para os conjuntos GBSMCS foram os cálculos teóricos da afinidade por próton de sistemas atômicos e moleculares, iônicos e neutros, das entalpias de liquefação de alguns solventes orgânicos rotineiros e das entalpias de hidratação de 29 compostos orgânicos diversos. Nas etapas de validação, observou-se de uma maneira geral, uma boa relação entre custo e benefício na utilização dos conjuntos de bases GBSMCS, obteveram-se desvios médios por volta de 0 até 20 kJ.mol, nas propriedades estudadas. Com as metodologias propostas neste trabalho e com a utilização dos conjuntos GBSMCS, determinou-se o perfil potencial da reação modelo de Suzuki-Miyaura tanto em fase gasosa como em fase solvatada de tetraidrofurano. Não se observou efeitos significativos nas estruturas dos estados estacionários caracterizados e nem nas DrG para as etapas de adição-oxidativa, transmetalação, eliminação-redutiva e isomerização. Contudo, observou-se que há efeitos consideráveis de solvatação para as espécies individuais. As etapas de adição-oxidativa e de eliminação-redutiva apresentaram-se como sendo etapas exergônicas e a etapa de transmetalação como sendo uma etapa endergônica tanto em fase gasosa como em tetraidrofurano. Abordou-se um mecanismo associativo em todas as etapas principais reacionais, contudo inferiu-se que a etapa de transmetalação tenha possíveis rotas mecanísticas dissociativas iônicas que serão estudadas em trabalhos futuros
Abstract: Using the implementation of the discretized generator coordinate method in atomic orbitals, atomic basis sets adapted to the pseudopotential core SBKJC were developed ( GBSMCS ), validated and used to study possible effects of tetrahydrofuran¿s solvation over a model Suzuki-Miyaura¿s mechanism. The methodologies adopted for the validation of GBSMCS basis sets were the theoretical calculations of proton affinities of atomic and molecular, ionic and neutral, systems, the liquefaction enthalpies of some common organic solvents and the hydration enthalpies of 29 organic compounds. In the validation steps a good relationship was abserved between cost and benefit in the use of GBSMCS basis set, average deviations around 0 to 20 kJ.mol for the properties studied. Applying the methodologies proposed in this research and using the GBSMCS atomic basis sets, the potential profile of the Suzuki- Miyaura¿s model mechanism was determinated in the gas and tetrahydrofuran phases. No significant tetrahydronfuran¿s solvation effects were observed for molecular stationarys state structures, neither for DrG for oxidative- addition, transmetallation, reductive-elimination and isomerization reaction steps. However, some strong solvation effects were observed for individual species. The oxidative-addition and reductive-elimination reaction steps were characterized as exergonic steps, but transmetallation reaction step was presented as an endergonic step, both in the gas and tetrahydrofuran phases. This work approaches an associative mechanism for all main reaction steps; however, we inferred that the transmetallation reaction step could have some ionic pathways and should be studied in future works
Doutorado
Físico-Química
Doutor em Ciências
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17

Gueogjian, Karina. "Funcionalização de cumarinas via reação de acoplamento de Suzuki-Miyaura de sais de organotrifluoroboratos de potássio." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-16082011-110745/.

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As cumarinas são compostos com potente atividade biológica. Foi explorada sua funcionalização, iniciando pela sua bromação, gerando o composto 3-bromocumarina, utilizado como material de partida para as reações de acoplamento do tipo Suzuki-Miyaura, que são uma das reações mais empregadas para a formação de ligação carbono-carbono, a qual utiliza paládio como catalisador e ácidos e ésteres borônicos como nucleófilo. Esses ácidos e ésteres borônicos possuem desvantagens, por isso foram substituídos pelos sais de organotrifluoroboratos de potássio, que são mais nucleofílicos, estáveis à umidade e à luz e não são higroscópicos. Assim, foi associada a catacterística reativa da cumarina para gerar derivados cumarínicos. Foram utilizados sais de ariltrifluoroboratos de potássio na primeira etapa e alquiniltrifluoroboratos de potássio na segunda etapa. Após o término destas duas etapas, foi utilizado o acoplamento de Sonogashira para a geração de um segundo material de partida, o 3-etiniltrimetilsililcumarínico, para poder sintetizar os 1,2,3-triazolilcumarínicos através da 1,3-dipolar cicloadição de Huisgen. Os 1,2,3-triazóis também possuem vasta atividade biológica, sendo de grande interesse sua preparação.
The coumarins are compounds with great biologic activity, for this reason in this dissertation we explored the functionalization beginning with bromination, generating the compound 3-bromocoumarin, used as starting material for the Suzuki-Miyaura cross-coupling reactions.The Suzuki-Miyaura cross-coupling reactions is one of the most employed protocol for carbon-carbon bond formation that use palladium as catalyst, boronic acid and ester as nucleophiles. But this boronic acid and ester have drawback and were substituted for potassium organotrifluoroborate salts that are more nucleophilic, moisture and light stable and are not hygroscopic. In this context, we associated the coumarin reactivity characteristic with the methodology mentioned above for create coumarin derivatives. We used potassium aryltrifluoroborate salts in the first step and potassium alkynyltrifluoroborate salts for the second step. After finished both steps mentioned before, we used the Sonogashira coupling to create the second starting material, the 3-((trimethylsilyl)ethynyl)-2H-chromen-2-one, so we could synthesize the 1,2,3-triazolyl coumarins through Huisgen 1,3-dipolar cycloaddtion. The 1,2,3-triazole also have a huge biologic activity, that represent a large interest for your preparation.
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18

Cella, Rodrigo. "Estudo visando à síntese enantiosseletiva da malevamida D e reações de Suzuki-Miyaura envolvendo espécies insaturadas de telúrio." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/46/46135/tde-25042008-103701/.

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Esta tese descreve, em dois diferentes capítulos, a síntese assimétrica da Malevamida D e a aplicação de compostos organotelúrio em reações de Suzuki-Miyaura. O primeiro capítulo refere-se ao estudo da síntese assimétrica da Malevamida D, um depsipeptídeo natural pertencente à família das dolastatinas, compostos estes com grande atividade citotóxica. As unidades DAP e MMMAH foram alcançadas em ótimos redimentos e estereosseletividades, utilizando-se reações de adição de crotil ou aliltrifluoroborato de potássio à aldeídos derivados da L-prolina e L-isoleucina, respectivamente. A elongação da cadeia da malevamida D se fez a partir de reações de esterificação e amidação; infelizmente não foi possível completar a síntese devido a problemas na última reação de acoplamento peptídico. O segundo capítulo descreve as reações entre teluretos aromáticos ou vinílicos e sais de organotrifluoroborato de potássio, mediadas por um catalisador de paládio. A partir destas reações de acoplamento cruzado tipo Suzuki-Miyaura foi possível obter-se 1,3-eninos, sistemas biarílicos, (E)- ou (Z)-estilbenos e 1,3-dienos. Todas as reações mostraram serem tolerantes a uma grande variedade de grupos funcionais e altamente estereoconservativas, nos casos envolvendo substratos vinílicos.
This thesis describes, in two different chapters, the asymmetric synthesis of malevamide D and the application of organotellurium compounds in Suzuki-Miyaura reaction. The first chapter refers to the asymmetric synthesis of malevamide D, a natural depsipeptide which belongs to the dolastatins family, and these compounds have a great interest due to theirs citotoxic activities. The DAP and MMMAH units were reached in excellent yields and stereoselectivities from 1,2-addition reaction of potassium crotyl or allyltrifluoroborate to aldehydes derivate from L-proline and L-isoleucine, respectively. The malevamide D elongation was made from reaction of esterification and amidation, unfortunately it was not possible finish the synthesis due to some problems in the last step of the total synthesis. The second chapter describes the reaction between aryl or vinyl tellurides and potassium organotrifluoroborate salts, mediated by a palladium catalyst. From this cross-coupling reaction type Suzuki-Miyaura was possible obtain 1,3-dienes, biarylic systems, (E)- or (Z)-stylbenes and 1,3-dienes. Al reactions showed to be tolerant to a wide range of functional groups and highly stereoconservative, in the cases involving vinylic substrates.
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19

Minard, Corinne. "Doubles couplages de Suzuki-Miyaura sélectifs sur des dérivés dihalogénés symétriques - Application à la synthèse de la ningaline B et de ses analogues." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00919884.

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La recherche de nouvelles molécules à visée thérapeutique est un enjeu majeur pour la communauté scientifique et actuellement, 60% des médicaments utilisés cliniquement sont des produits naturels ou leurs analogues. Dans ce contexte, afin d'être capable de générer rapidement une bibliothèque de composés, le développement d'outils de synthèse efficaces est fondamental et c'est dans cette optique que s'inscrit le travail mené au cours de cette thèse. Les produits d'origine marine sont une source d'inspiration considérable dans le domaine de la création de nouveaux médicaments. Lors de ce travail, une attention particulière a été accordée à la ningaline B et à ses analogues avec pour objectif de mettre au point une voie d'accès simple et efficace. En effet, si la capacité de la forme hexaméthyléther à reverser la résistance aux anticancéreux par inhibition de la glycoprotéine-P a déjà été rapportée dans la littérature, l'étude d'analogues n'a été que peu exploitée.Dans ce contexte, une voie de synthèse reposant sur une étape clé de double couplage de Suzuki-Miyaura sur un dérivé (pseudo)dihalogéné symétrique a été proposée. Cette étape a fait l'objet d'une étude approfondie en envisageant deux approches. La première approche, basée sur des travaux antérieurs réalisés au laboratoire, a été de type simultané. Ainsi, à la manière d'une réaction multicomposante, tous les réactifs sont introduits dès le départ dans le milieu réactionnel. Cette méthode a montré des résultats intéressants dans le cas où deux dérivés borés électroniquement différents sont employés. En revanche, il a été montré que l'utilisation d'espèces borés électroniquement similaires était peu viable avec l'obtention d'un mélange statistique en produits de dicouplage. Toutefois, la préparation des cibles visées requérant l'utilisation d'aryles borés riches en électrons, une autre approche, séquentielle, a été envisagée. Après un travail d'optimisation sur des substrats simplifiés, avec pour objectif de disposer de conditions efficaces, adaptables, faciles avec des réactifs standards, une méthode de monoarylation de dérivés (pseudo)dihalogénés symétriques a été mise en place. Le champ d'application a ensuite été élargi en incluant les noyaux pyrroles nécessaires à la synthèse de la ningaline B et de ses dérivés. Ces travaux ont permis d'accéder aux molécules ciblées. En effet, une fois, les teraryles préparés, quelques étapes de manipulations fonctionnelles permettront d'avoir rapidement accès à de nombreux analogues. D'autre part, les motifs pouvant être obtenus par ce type de séquence réactionnelle pourraient être facilement dérivatisables afin de générer une bibliothèque d'analogues.
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20

Kendall, Christopher Nicholas Owen. "The directed ortho metalation - Suzuki-Miyaura cross-coupling connection, towards the total synthesis of dehydrorabelomycin." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0020/MQ54462.pdf.

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21

Braga, Ataualpa Albert Carmo. "Estudos teoricos da sintese da (-) - monatina e de reações de acoplamento-cruzado de Suzuki-Miyaura." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248947.

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Orientador : Nelson Henrique Morgon
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
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22

Keith, Adam J. "Ion-tagged Phosphines for Catalytic Reactions in Ionic Liquids." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1407960203.

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23

Nichele, Tatiana Zarichta. "Acoplamento Suzuki-Miyaura: uso de glicerol para síntese de ésteres arilboronatos e como solvente, e síntese de atropoisômeros." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/63141.

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Nesta tese a reação de Suzuki-Miyaura será abordada em três diferentes enfoques: utilização de ésteres glicerolarilboronatos, emprego de glicerol como meio reacional e síntese de atropoisômeros a partir de ligantes nitrogenados N-N’ quirais. Primeiramente, a reação do glicerol com ácido fenilborônico proporcionou uma mistura de ésteres cíclicos, glicerol 1,2- fenilboronato (80 %) e glicerol 1,3-fenilboronato (20 %). Os ésteres glicerol fenilforonatos foram empregados em reações de Suzuki-Miyaura catalisadas por paládio com haletos de arila e as respectivas biarilas foram obtidas com rendimentos elevados (> 90 %). Não foi necessário utilização de excesso do composto organoborado e as reações de acoplamento Suzuki-Miyaura foram realizadas mediante precursor catalítico preparado in situ a partir de acetato de paládio e trifenilfosfina sob condições reacionais brandas. A atividade catalítica foi obtida com TON de 62.000. Posteriormente, o uso de glicerol como meio reacional foi eficaz para a o acoplamento de Suzuki-Miyaura que foi estudado. A reação entre brometos de arila e de ácidos arilborônicos, utilizando glicerol como solvente, forneceu um protocolo ambientalmente menos danoso, eficiente e prático para a síntese biarilas. O glicerol foi usado como solvente utilizando baixas quantidades de catalisador (0,5-1 mol%) produzindo produtos de acoplamento com rendimentos de moderados a elevados (46-99 %). Os produtos foram facilmente isolados através de extração simples e o catalisador pôde ser reutilizado. Finalmente, a síntese de uma série de ligantes piridina-imina e quinolinaimina N-N’ quirais foi descrita. A eficácia destes ligantes N-N’ quirais foi investigada utilizando paládio como precursor catalítico em reação de Suzuki assimétrica entre o ácido 2-etóxinaftilborônico e 1-iodonaftaleno. O produto de acoplamento foi obtido com máximo de 25 % de enantiosseletividade e 91 % de conversão em condições reacionais brandas (50 oC e 6 h).
In this thesis, the Suzuki-Miyaura reaction is discussed in three different approaches: using glycerol arylboronates esters, glycerol application as reaction medium and synthesis of atropisomers from chiral N-N' ligands. First, the reaction of glycerol with phenylboronic acid provided a mixture of cyclic glycerol esters, glycerol 1,2-phenylboronate (80 %), and glycerol 1,3- phenylboronate (20 %). The glycerol phenylboronates were applied to the Pdcatalyzed Suzuki-Miyaura cross-coupling reactions with aryl halides, affording the corresponding biphenyl products in high yields. Excess glycerol phenylboronate was not required, and the Suzuki-Miyaura coupling reaction employed a simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine under mild reaction conditions. The catalytic activity was obtained 62.000 of TON. Second, the use of glycerol as efficient reaction medium for Suzuki- Miyaura reaction was studied. The reaction of aryl bromides with arylboronic acids using glycerol as solvent provides an environmentally benign, efficient and practical protocol for the synthesis of biaryl products. We have found that glycerol can used as solvent using low amounts of catalyst (0.5 mol%) and giving the coupling products in moderate to high yields (46-99 %). The products were easily removed by simple extraction and under the catalyst medium was reused. In the last part, the synthesis of a series of pyridine-imine and quinolineimine chiral N-N’ ligands was described. The efficacy of these chiral N-N’ ligands was investigated in the palladium catalysed asymmetric Suzuki coupling between 2-ethoxynaphthylboronic acid and 1-iodonaphthalene, leading to a maximum of 25 % enantioselectivities at 91 % conversion under mild reactions conditions (50 oC and 6 h).
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24

Crockett, Michael. "TheDevelopment of Iron Catalysts for Suzuki-Miyaura Cross-Coupling and the Reactivity Discovered Along the Way:." Thesis, Boston College, 2020. http://hdl.handle.net/2345/bc-ir:108946.

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Thesis advisor: Jeffery A. Byers
This dissertation discusses the development of iron-based catalysts for Suzuki-Miyaura cross-coupling reactions and some of the unique reactivity that was discovered as a direct result of these studies. Chapter one will review the area of iron-catalyzed cross-coupling with an emphasis placed on areas where iron provides complimentary reactivity to other metals. Chapter two will detail the initial discovery of conditions that allow for iron-catalysts to participate in the cross-coupling of aryl boronic esters and alkyl halides. Chapter three will discuss the the development of ligands for iron that allow for more general cross-coupling reactivity to be observed. Finally, chapter four will discuss the unique C-H funtionalization reactivty that has been observed as byproducts in chapters two and three. Digging deeper into this reactivty lead to the discovery of a completely novel three-component coupling reaction mediated by the iron complexes discovered in chapter three
Thesis (PhD) — Boston College, 2020
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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25

Lai, Ping-Shan. "Directed ortho metalation-boronation Suzuki-Miyaura cross coupling leading to synthesis of azafluorenol core liquid crystals." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/511.

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Sun, Lijie. "Synthesis of atropisomeric 1-Naphthamide-Derived phosphines and application for asymmetric heck and Suzuki-Miyaura reactions /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202009%20SUN.

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Amaral, Mônica Franco Zannini Junqueira. "Funcionalização de 2-(S)-isopropil-pirimidinonas através de reações de Suzuki-Miyaura, Sonogashira e cicloadição azida-acetileno: síntese de derivados triazólicos e precursores de β-aminoácidos." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-26012011-160334/.

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Nesta monografia foram desenvolvidas metodologias sintéticas para a funcionalização das 2-(S)-isopropil-5-iodo-pirimidinonas, utilizando a reação de acoplamento cruzado de Suzuki-Miyaura e a reação de cicloadição azida-acetileno com cobre, através de estratégias simples e eficientes que permitiram a preparação de uma série de compostos com grande diversidade estrutural. Inicialmente descreve-se a síntese da 2-(S)-isopropil-5-iodo-pirimidinona (S)- 3, a partir da (S)-asparagina enantiomericamente pura 1, um aminoácido barato e de fácil acesso, produzindo na primeira etapa o 2-(S)-isopropil-peridropirimidinona-6- ácido carboxílico (2S,6S)-2, que reagindo com diacetoxiiodo benzeno/iodo e BF3.OEt2, gera a pirimidinona (S)-3. Em seguida, preparou-se uma série de 2-(S)-isopropil-5-aril-pirimidinonas (S)- 6a-q e 2-(S)-isopropil-5-alquinil-pirimidinonas (S)-7a-q, através da reação de acoplamento cruzado de Suzuki-Miyaura, sob catálise de paládio, utilizando aril- (4aq) e alquiniltrifluoroboratos de potássio (5a-q), respectivamente. Desta forma sintetizou-se uma variedade de pirimidinonas com alterações programadas de substituintes na posição 5 do anel, com rendimentos de 15% a 95%. Ainda a fim de obter algumas pirimidinonas com substituintes acetilênicos alquílicos 9a-f, utilizou-se a metodologia de acoplamento de Sonogashira. Em todos os casos obtiveram-se bons rendimentos. Dando sequência ao projeto, sintetizou-se as 2-(S)-isopropil-pirimidinonas funcionalizadas na posição C5 com anéis triazólicos substituídos na posição N1 (S)- 11a-k, através da reação de cicloadição azida-acetileno utilizando CuI como fonte de cobre e ondas ultra-sônicas como fonte de energia. Preparou-se diversos compostos, todos com rendimentos variando de 79% a 87% em 5 minutos de reação. Por último, através da redução da dupla ligação endocíclica dos compostos (S)-6a, 6b, 6g, 6l e 6n e posterior hidrólise utilizando radiação microondas proporcionou a obtenção de α-aril β-aminoácidos altamente enantioenriquecidos.
This monograph shows the development of a synthetic methodology for the functionalization of 2-(S)-isopropyl-5-iodo-pyrimidinones using either Suzuki-Miyaura cross-coupling reactions or cycloaddition reactions of azide-acetylenes with copper, through a simple and efficient pathway enabling the preparation of a series of structurally diverse compounds. This paper begins by describing the synthesis of 2-(S)-isopropyl-5-iodopyrimidinones (S)-3, from enantiomerically pure (S)-asparagine 1. This inexpensive and readily available amino acid forms 2-(S)-isopropyl-perhidropyrimidinone-6- carboxylic acid (2S, 6S)-2, which is reacted with DIB / iodine and BF3·OEt2 to form pyrimidinone (S)-3. Using palladium-catalyzed Suzuki-Miyaura cross-coupling reactions, a series of 2-(S)-isopropyl-5-arylpyrimidinones (S)-6a-q and 2-(S)-isopropyl-5- alkynylpyrimidinones (S)-7a-q were prepared using potassium aryl- (4a-q) and alkynyltrifluoroborates (5a-q), respectively. With this reaction, a variety of pyrimidinones with different substituents at position 5 of the ring were synthesized, with yields ranging from 15% to 95%. The Sonogashira coupling reaction was used to prepare pyrimidinones with alkyl acetylenic substituents (S)-9a-f, giving good yields in all cases. 2-(S)-Isopropylpyrimidinones were then functionalized in the C5 position with N1 (S)-11a-k substituted triazole rings. These functionalizations were performed by the cycloaddition of azide-acetylenes using CuI and ultrasonic waves, which provided enough energy to reduce the reaction time to only five minutes. Several different variations of this compound were prepared, all with yields between 78% and 87%. Finally, the endocyclic double bonds in compounds (S)-6a, 6b, 6g, 6l and 6n were reduced, followed by a hydrolysis using microwave radiation to afford the highly enantioenriched α-aryl β-amino acids.
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28

Santarsiere, Alessandro. "A new total synthesis of myricanol : the influence of an ene-yne system." Electronic Thesis or Diss., Strasbourg, 2024. https://publication-theses.unistra.fr/public/theses_doctorat/2024/Santarsiere_Alessandro_2024_ED222.pdf.

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L'objectif principal de cette thèse de doctorat est la synthèse totale du myricanol, un composé naturel important aux activités biologiques intéressantes. En particulier, ses remarquables propriétés anti-Alzheimer en font un candidat potentiel pour le traitement de diverses taupathies, car il est capable de réduire les niveaux de protéine Tau qui ont tendance à s'accumuler sous forme phosphorylée dans certaines maladies neurodégénératives.. Actuellement, seules trois synthèses racémiques du (+/-)-myricanol sont rapportées dans la littérature. Tout d'abord, cette thèse vise principalement à explorer les conditions optimales pour rendre la cyclisation moins défavorable en utilisant un séco-précurseur insaturé et donc "rigide" en limitant les variations des degrés de liberté conformationnelles pendant la cyclisation. Deux approches synthétiques ont été explorées au cours de cette thèse, d’une part l'étape de macrocyclisation est réalisée à partir d’un système biarylique fonctionnalisé, d’autre part, l'étape de macrocyclisation est effectuée sur un diarylheptanoïde linéaire
The main objective of this thesis is the total synthesis of myricanol, a natural compound with significant biological activities. In particular, its remarkable anti-Alzheimer's properties make it a potential drug for the treatment of various tauopathies, as it has the ability to reduce levels of tau protein that tend to pathologically accumulate in phosphorylated forms in certain neurodegenerative diseases. Actually only three synthesis of racemic (+/-) - myricanol have been reported in the literature. Firstly, this thesis aims primarily to investigate the optimal conditions to make cyclization less unfavorable using an unsaturated and thus "rigid" seco-precursor to limit conformational degrees of freedom during cyclization. Two main synthetic approacheshave been explored in the course of this thesis, on one side, the macrocyclization involves the properly functionalized biaryl system, on the other side the macrocyclization is performed on a linear diarylheptanoid
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29

Bochicchio, Antonella. "Towards the atropo-stereoselective total synthesis of myricanol." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAF004/document.

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Le myricanol est un [7,0]-métacyclophane naturel qui appartient à la famille des diarylheptanoïdes cycliques et qui possède des propriétés structurales et biologiques intéressantes (activité anti-Alzheimer ou anticancéreuse). L’objectif de ce travail de thèse est la préparation ambitieuse en voie racémique puis atropostéréosélective du myricanol, rendue délicate de part la tension de cycle existante. Pour se faire, deux nouvelles approches rétrosynthétiques ont été considérées. Une première route racémique a été envisagée et a permis de préparer le macrocycle par le biais d’une réaction de métathèse croisée suivie d’une réaction de Suzuki-Miyaura domino intramoléculaire avec un rendement de 2.55% en 11 étapes. Une autre voie racémique a également été explorée où la préparation du noyau biarylique du myricanol a été envisagé par une réaction de couplage intermoléculaire métallo-catalysée suivie d’une réaction de métathèse cyclisante. Des intermédiaires avancés ont également été préparés
The myricanol, a natural [7.0]-meta-cyclophane which belongs to the family of strained and cyclic diarylheptanoids, possess an interesting structure and attractive biologically activities (anti Alzheimer and anti cancer properties). Actually only two synthesis of racemic (+/-)-myricanol have been reported in the literature. The goal of this research was to prepare this strained cyclophane in a racemic and then in an atropostereoselective route taking into account the challenging ring closure. Thus a linear diarylheptanoid was prepared using an efficient cross-metathesis reaction followed by an intramolecular Suzuki-Miyaura domino reaction giving rise to the desired cyclophane with 2.55% overall yield in 11 steps. On the other side, the biaryl core of myricanol was envisaged by an intermolecular metallo-catalysed coupling reaction between already highly functionalized fragments, followed by a ring closure metathesis. Two advanced intermediates were already attempted
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30

Chen, Donghuang. "Well-defined iron(II) catalysts for alkyl-aryl and alkyl-alkyl Suzuki-Miyaura and Kumada cross-couplings." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASF081.

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Ce travail de thèse vise à réaliser la formation de liaisons C(sp³)-C(sp²) et C(sp³)-C(sp³) par couplages croisés de Suzuki-Miyaura (S-M) et de Kumada à l'aide de catalyseurs de fer, nouvellement développés, et en mettant l'accent sur l'étude du potentiel applicative de ces catalyseurs en synthèse. Ce travail se concentre aussi sur la mise au point d'une méthode efficace et sélective de 1,2-dicarbofonctionnalisation d'alcènes promue par ces catalyseurs. Le chapitre 1 présente les premières découvertes des couplages croisés médiés par le fer et le développement de catalyseurs de fer pour les couplages croisés de S-M et de Kumada. Les formations de liaisons C(sp²)-C(sp²), C(sp²)-C(sp³) et C(sp³)-C(sp³) seront couvertes. La conception de ligands adaptés et les études mécanistiques ont joués un rôle crucial dans le développement du domaine. La section suivante présente l'état de l'art de la méthode de 1,2-dicarbofonctionnalisation des oléfines catalysées par les métaux abondants, en soulignant les stratégies développées pour surmonter les réactions secondaires indésirables. Le chapitre 2 traite de la réaction de S-M, dont l'utilisation s'est largement répandue en raison de sa large applicabilité, ainsi que de la stabilité, de la disponibilité et de la faible toxicité des réactifs organoborés. Tant en recherche académique qu'en l'industrie, la plupart des couplages de S-M sont dominés par des catalyseurs à base de palladium et de nickel. Récemment, le fer a fait l'objet d'une attention particulière en raison de sa forte abondance et de sa nature respectueuse de l'environnement. Malgré le rôle crucial du fer dans l'offre d'une catalyse plus durable pour le couplage de S-M, ce dernier impliquant des partenaires hybridés sp³ reste rare et se heurte à d'importantes limitations en termes de champ d'applications. Ce chapitre présente le développement d'un catalyseur de fer(II), versatile et de structure bien définie, qui réalise avec succès les couplages alkyle-aryle et alkyle-alkyle de S-M entre des halogénures d'alkyle et des esters boroniques (hétéro)arylés ou des dérivés boranes alkylés. Ces couplages ont été réalisés dans des conditions douces et ont montré une large compatibilité avec diverses fonctionnalités, y compris des N-, O- et S-hétérocycles importants en chimie médicinale. Les halogénures d'alkyle primaires, secondaires (Br, Cl, I) et tertiaires, ainsi que les esters boroniques neutres, riches et pauvres en électrons, de même que les boranes d'alkyle 1° et 2° sont compatibles et ont donné des rendements élevés à excellents. Des solvants plus écologiques ont été utilisés lors de la synthèse d'intermédiaires pharmaceutiques clés et d'un candidat médicament avec des rendements élevés, ce qui démontre un fort potentiel applicatif pour une production industrielle à grande échelle. Le chapitre 3 présente l'application du couplage croisé de S-M dans une méthode de 1,2-alkylarylation d'oléfines à trois composants, promue par un catalyseur de fer(II). Cette méthode facilite la formation de deux liaisons carbone-carbone en une seule étape de synthèse et représente le premier exemple de couplage de S-M combiné à une fonctionnalisation d'alcènes, conduisant sélectivement au produit de fonctionnalisation-1,2 alkyle-aryle. Bien que la méthodologie actuelle soit limitée par la nécessité d'un excès d'oléfines (10 équiv.) et d'esters boroniques donneurs en électrons, l'utilisation de réactifs borés démontre un potentiel pour des applications synthétiques plus larges. Le chapitre 4 étend l'application du catalyseur de fer(II) développé dans les chapitres 2 et 3, en démontrant son efficacité remarquable dans la réaction de couplage croisé de Kumada entre des halogénures d'alkyle hybridés sp³ et des réactifs organomagnésiens hybridés sp² et même sp³ dans des conditions douces. Cela souligne la grande polyvalence de ce catalyseur qui facilite le couplage de divers centres carbonés hybridés sp² et sp³, sans le besoin de conditions drastiques
This PhD research aims to achieve challenging C(sp³)-C(sp²) and C(sp³)-C(sp³) bond formations through Suzuki-Miyaura and Kumada cross-couplings using newly-designed iron-based catalysts, with an emphasis on their potential for synthetic applications. This work also focuses on achieving efficient and selective 1,2-dicarbofunctionalization of unactivated alkenes promoted by these catalysts. Chapter 1 primarily introduces the early discoveries of iron-mediated cross-couplings and the development of iron-based catalysts in Suzuki-Miyaura and Kumada cross-couplings, covering C(sp²)-C(sp²), C(sp²)-C(sp³), and C(sp³)-C(sp³) bond formations. The design of bespoke ligand and mechanistic investigations have played a crucial role in the development of this field. The following section introduces the state-of-the-art in earth-abundant metal-catalyzed 1,2-dicarbofunctionalization of olefins, highlighting strategies developed to overcome undesired side reactions. Chapter 2 covers the Suzuki-Miyaura reaction, which has gained widespread use due to its broad applicability, along with the stability, availability, and low toxicity of organoboron reagents. Most Suzuki-Miyaura couplings (SMC), both in academia and industry, are dominated by palladium and nickel catalysts. Recently, iron has garnered significant attentions due to its earth abundance and environmentally friendly nature. Despite the crucial role of iron in offering more sustainable catalysis for Suzuki-Miyaura coupling, iron-catalyzed SMC involving sp³-hybridized systems remains rare and faces significant scope limitations. This chapter reports on the development of a versatile, well-defined iron(II) catalyst that successfully facilitated C(sp3)-C(sp2) and C(sp3)-C(sp3) SMC of alkyl halide electrophiles with (hetero)aryl boronic esters and alkyl borane nucleophiles, respectively. These couplings were carried out under mild reaction conditions, exhibited broad functional group compatibility - including various medicinally important N-, O-, and S-based heterocycles. Primary, secondary alkyl halides (Br, Cl, I), and tertiary alkyl chlorides, as well as electron-neutral, electron-rich, and electron-poor boronic esters, alongside 1° and 2° alkyl boranes all were tolerated with high to excellent yields. Greener solvents were used in the synthesis of key intermediates relevant to pharmaceuticals and potential drug candidates with high yields, demonstrating significant potential for large-scale industrial production. Chapter 3 introduces the application of Suzuki-Miyaura cross-coupling in the three-component 1,2-alkylarylation of unactivated olefins, using a well-defined iron(II) catalyst. This method facilitates the formation of two carbon-carbon bonds in a single synthetic step and represents the first example of combining Suzuki-Miyaura cross-coupling and 1,2-functionalization of unactivated alkenes, selectively yielding the desired 1,2-alkylarylation product. Although the current methodology is limited by the requirement for an excess of olefins (10 equiv.) and electron-donating boronic esters, the use of boron reagents demonstrates a potential for broader synthetic applications. Chapter 4 extends the application of the iron(II) catalyst developed in Chapters 2 and 3, demonstrating its remarkable efficacy in catalyzing the Kumada cross-coupling reaction between C(sp³)-hybridized alkyl halides and either C(sp²)- or even C(sp³)-hybridized organomagnesium reagents under mild conditions. This achievement underscores the broad versatility of this catalyst in facilitating the coupling of diverse carbon centers, including both sp² and sp³ hybridizations, without requiring harsh conditions
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31

Sousa, Ariane Cavalcante dos Santos. "Síntese de 2,5-diarilfuranos: potenciais sondas fluorescentes usadas como biomarcadores em malária." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/9/9138/tde-17112016-141313/.

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A malária é uma das principais causas de morte em muitos países de clima tropical, matando mais de 438 mil pessoas anualmente em todo o mundo. Desta forma, o objetivo do presente trabalho foi sintetizar compostos fluorescentes 2,5- diarilfuranos através da reação de acoplamento cruzado tipo Suzuki-Miyaura e acoplar ao fármaco Primaquina para utilizá-los laboratorialmente como biomarcadores específicos, carreadores de substâncias, parasiticidas, além do desenvolvimento de novo método diagnóstico. Através deste tipo de reação, foram sintetizados 3 compostos fluorescentes: a sonda 3-AFA, 3-AFA ala e a 4-AFAPQ. Inicialmente foram utilizadas células primárias, células da linhagem RAW 264.7 e células eritrocíticas, estas provenientes de camundongos Balb/c inoculados pela via intraperitoneal com 106 EI/mL de P. berghei ANKA GFP. Os compostos fluorescentes sintetizados 3-AFA e 3-AFA ala foram incubados com as células acima citadas e verificou-se a capacidade de as sondas penetrarem e marcarem células sadias e/ou infectadas. A aquisição dos resultados foi realizada por meio de citometria de fluxo e microscopia confocal. A partir daí, utilizou-se também sangue humano proveniente de doação que foi infectado com P. falciparum 3D7. A análise dos resultados realizada com microscopia de fluorescência e testes de EC50 com estes eritrócitos, além de células HepG2. As sondas 3-AFA e 4-AFAPQ foram incubadas com estas células para avaliar a ação parasiticida, bem como a citotoxicidade destes compostos. Nossos resultados mostraram que as sondas 3-AFA e 3-AFA ala não foram capazes de penetrar os macrófagos. Entretanto, foram capazes de atravessar a membrana dos eritrócitos infectados marcando o parasita. Quando os compostos 3- AFA e a 4-AFAPQ foram inseridos em eritrócitos humanos infectados pelo P. falciparum 3D7, foi possível observar que ambos marcaram o parasita em suas 3 fases. Mas resultados de EC50 mostraram que os compostos não possuem efeito parasiticida. E podemos concluir que estes compostos não são citotóxicos ás células possuindo então, um potencial em serem estudados mais a fundo, com algumas modificações em suas estruturas para melhorar assim, sua eficiência quanto a seletividade. Diante destes compostos potencialmente fluorescentes, foi possível também desenvolver um novo método de diagnóstico rápido simples e barato que pode possibilitar o alcance em locais aonde os métodos convencionais de microscopia não chegam.
Malaria is a major cause of death in many tropical countries, killing over 438 thousand people annually worldwide. Thus, the objective of this study was to synthesize fluorescent compounds 2,5-diarylfuranes through cross-coupling reaction like Suzuki-Miyaura and engage the drug Primaquine to use them as laboratory specific biomarkers, carriers of substances, parasiticide, and the development new diagnostic method. Through this type of reaction, three fluorescent compounds were synthesized: probe 3-AFA, 3-AFA ala and 4-AFAPQ. Initially were used primary cells, strain RAW 264.7 cells line and erythrocytic cells, those derived from Balb/c mice inoculated intraperitoneally with 106 IE/mL of P. berghei ANKA GFP. The synthesized fluorescent compounds 3-AFA and 3-AFA ala were incubated with the above said cells and found the ability of penetrating probes and mark healthy cells and/or infected. The acquisition of the results was performed by flow cytometry and confocal microscopy. From there, it was also used human blood from that donation was infected with P. falciparum 3D7. The analysis performed with fluorescence microscopy and EC50 these tests with erythrocytes, and HepG2 cells. The probes 3-AFA and 4-AFAPQ were incubated with these cells to evaluate the parasiticidal activity and cytotoxicity of these compounds. Our results showed that the probes 3-AFA and 3-AFA ala were not able to penetrate macrophages. However, they were able to pass the membrane of the parasite infected erythrocytes marking. When the fluorescents probes 3-AFA and 4- AFAPQ (coupled Primaquine) were inserted into human erythrocytes infected with P. falciparum 3D7, it was observed that both marked the parasite in her 3 phases. But EC50 results showed that the compounds do not have parasiticidal effect. And we can conclude that these compounds are not cytotoxic to the cells having then a potential be studied further, with some modifications in their structures to improve thus efficiency and selectivity. Given these potentially fluorescent compounds, it was possible to develop a new method of simple and inexpensive rapid diagnosis that can enable the range in places where conventional methods of microscopy not arrive.
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32

Peramo, Arnaud. "Modification sélective de protéines en milieu biologique par réaction de Suzuki-Miyaura nanocatalysée PLGA-PEG-supported Pd nanoparticles as efficient catalysts for Suzuki-Miyaura coupling reactions in water Selective modification of a native protein in a patient tissue homogenate using palladium nanoparticles A Self-Assembling Palladium-Loaded Calixarene as a Potent Catalyst for the Suzuki-Miyaura Cross-coupling Reaction in Water." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS600.

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Les nanotechnologies ont ouvert de nouvelles perspectives pour l’administration ciblée des médicaments. Les approches actuelles en nanomédecine sont basées sur l’encapsulation d’un principe actif dans un nano-vecteur. Nous proposons dans ce travail l’utilisation de nanoparticules non plus pour adresser un médicament encapsulé vers sa cible, mais pour manipuler une protéine d’intérêt en milieu biologique, ce qui constitue une nouvelle stratégie thérapeutique. Avec cet objectif, nous avons identifié une formulation de nanoparticules de palladium, stable, non toxique et dotée d’un pouvoir catalytique remarquable de la réaction de Suzuki-Miyaura. Ce nano-catalyseur permet, en utilisant un dérivé du bore approprié, de greffer des résidus aromatiques sur des acides aminés halogénés dans un tampon phosphate à température et pH physiologiques. En parallèle, la formulation sous forme de nanoparticules de calixarenes fonctionnalisés par des complexes carbéniques du palladium a été également étudiée. Ce nano-réacteur permet d’effectuer dans l’eau et à température ambiante une réaction d’arylation d’amino acides halogénés de manière très efficace. Nous montrons qu’il est possible grâce à ces nanoparticules de modifier sélectivement par une liaison covalente, la thyroglobuline, une protéine naturelle halogénée, impliquée dans la maladie de Basedow et dans certains cancers de la thyroïde. L’absence de modèle cellulaire exprimant la protéine nous a conduit à tester la réaction dans un homogénat d’organe provenant de l’exérèse chirurgicale de la thyroïde chez un patient de la maladie de Basedow. Le couplage de la thyroglobuline par réaction de Suzuki-Miyaura a pu être détecté par analyse protéomique grâce au marquage par un cycle aromatique simple, et par western blot à l’aide d’une sonde biotine autorisant une détection par immuno-essai. En conclusion, la thèse apporte la démonstration de la formation sélective d’une liaison C-C sur une protéine par des nanoparticules de palladium dans un milieu biologique complexe et en conditions physiologiques. Ces résultats pourraient ouvrir la voie à de nouvelles options thérapeutiques permettant de controler le taux de thyroglobuline dans le cas d’une dérégulation hormonale
Nanotechnology has opened up new perspectives for targeted drug delivery in the treatment of severe diseases. Current approaches in nanomedicine are based on the encapsulation of an active drug in a nanocarrier. In the present study, we have used nanoparticles not to address an encapsulated drug to a target tissue, but for manipulating a protein of interest in a complex biological medium. With this aim, we have identified a stable, non-toxic palladium nanoparticle formulation, embedding a remarkable catalytic activity on the Suzuki-Miyaura reaction. This nano-catalyst allows by using an appropriate boron derivative to couple aromatic residues onto halogenated amino acids in a phosphate buffer at physiological pH. By the same way, the formulation as nanoparticles of calixarene derivatives functionalized with palladium carbene complexes was studied. This new nano-reactor allowed similarly the arylation reaction of halogenated amino acids in water and at ambient temperature in a very efficient manner.We showed that it is possible, thanks to these nanoparticles, to modify selectively by a covalent bond the thyroglobulin, a halogenated natural protein, implicated in Graves' disease and in certain thyroid cancers. The absence of a protein-expressing cellular model led us to test the reaction in an organ homogenate from surgical thyroid excision from a Graves' disease patient. The coupling of thyroglobulin by Suzuki-Miyaura reaction was detected by proteomic analysis by labeling with a simple aromatic ring and by western blotting using a biotin probe allowing detection by immunoassay. In conclusion, the study undertaken in the thesis has shown the selective formation of a CC bond onto a natural protein in a complex biological medium and under physiological conditions, by using palladium nanoparticles. This result paves the way for new therapeutic perspectives to control the level of thyroglobulin in the case of hormonal dysregulation
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33

Zink, Laura. "Synthèse de dérivés 5-nitroimidazoles à potentialités anti-infectieuses." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM5506/document.

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L'objectif de ce travail consiste en la synthèse de nouveaux 5-nitroimidazoles fonctionnalisés à visée thérapeutique. Dans un premier temps, l'étude de la réactivité du 4-bromo-1,2-diméthyl-5-nitro-1H-imidazole vis-à-vis du couplage de Suzuki-Miyaura sous irradiation micro-ondes a permis la synthèse de nouveaux produits substitués en position 4 par différents groupements aryle ou styryle. Dans un second temps, la réactivité LD-SRN1 a été étudiée entre le 4-[4-(chlorométhyl)phényl]-1,2-diméthyl-5-nitro-1H-imidazole et différents nucléophiles centrés sur l'atome de carbone ou de soufre. Cette étude a révélé l'importance de la température dans l'activation de la réaction par transfert monoélectronique. De nouveaux dérivés substitués en position 4 par divers groupements sulfonyles ont ensuite été synthétisés, par réactions SN2 et SNAr entre des dérivés 5-nitroimidazolés et différents anions sulfinates. Cette synthèse a été suivie par la mise au point de tests biologiques sur Trichomonas vaginalis. L'activité trichomonacide a été évaluée sur certaines de ces molécules, à l'origine de relations structure-activité montrant l'influence de la position du groupement sulfonyle substituant le noyau 5-nitroimidazole. La dernière partie de ce travail décrit une réaction de O-arylation pallado-catalysée inattendue et originale, d'un dérivé fluoré en série nitro(o-nitrophényl)imidazole impliquant des acides arylboroniques dans les conditions opératoires de la réaction de Suzuki-Miyaura
The aim of this work consists of the synthesis of new potentially bioactive functionalized 5-nitroimidazoles. Initially, the reactivity study of the 4-bromo-1,2-dimethyl-5-nitro-1H-imidazole under microwave-assisted Suzuki-Miyaura cross-coupling conditions gave new derivatives substituted by various aryl or styryl groups in 4-position. In a second step the 4-[4-(chloromethyl)phenyl]-1,2-dimethyl-5-nitro-1H-imidazole was prepared in order to study LD-SRN1 reactivity with different carbon and sulphur centered nucleophiles. This study pointed the role of the temperature for the electron transfer reactions. Then, new 4-position sulfonyl substituted derivatives were synthesized by SN2 and SNAr reactions between sulfinate anions and three substrates in 5-nitroimidazole series. This synthesis was followed by the development of biological assays on Trichomonas vaginalis. This assay was performed on some of these molecules, which revealed a relation between the structure and the position of the sulfonyl group and the antitrichomonas activity. The last part of this work describes an unexpected and original palladium-catalyzed O-arylation in fluorinated nitro(o-nitrophenyl)imidazole series involving arylboronic acids under Suzuki-Miyaura cross-coupling reaction conditions
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34

Valdivia, Giménez Victoria. "Nuevas aplicaciones de los derivados quirales de azufre : organocatalisis, sintesis enantioselectiva de calciomimeticos y acoplamiento de Suzuki-Miyaura." Strasbourg, 2010. http://www.theses.fr/2010STRA6009.

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La conception de processus stéréosélectifs qui permettent l'accès à des composés chiraux avec une pureté optique élevée est aujourd'hui l'un des domaines les plus importants dans la synthèse organique. Le principal objectif de cette thèse réside dans le développement de nouvelles méthodologies hautement modulaires pour la préparation de composés d'intérêt biologique ou synthétique à l'aide de dérivés chiraux du soufre. 1 Un des résultats, le plus notable, a été l'élaboration d'une méthode générale de synthèse énantiodivergente de sulfinates diastéréoisomèriquement purs et leur utilisation ultérieure comme agents chiraux de sulfinylation: la méthode de la Diacétone-D-glucose (DAG) La méthode DAG a été utilisée pour : −La préparation de sulfoxydes(1),2 et bis-sulfoxydes à symétrie C2(2, 3) 3, qui ont démontré être d'excellents ligands neutres dans un procédé organocatalytique de préparation d'allylamines chirales. −La synthèse énantiosélective du NPS-R-568, une α-méthylbenzylamine chirale avec une activité calciomimétique et son analogue trifluorométhylé, en utilisant l'isopropylsulfinamide 4 comme inducteur chiral. 4 −La synthèse de biarylsulfoxydes (5) à travers un couplage asymétrique de Suzuki-Miyaura. La structure des produits préparés à été modulé pour synthétiser différents ligands dans la catalyse et l'organocatalyse asymétrique
The design of stereoselective processes that allow access to chiral compounds with high optical purity is today one of the areas of greatest importance in organic synthesis. The main objective of this PhD was the development of highly modular new methodologies for the preparation of compounds of biological or synthetic interest using chiral sulfur derivatives. 1 One of the most notable result is the development of a general method for enantiodivergent synthesis of diastereomerically pure sulfinates and their subsequent use as chiral sulfinylation agents : the method of Diacetone-D-glucose (DAG) The DAG has been exploited for: −Preparation of differents sulfoxides (1),2 and bis-sulfoxides with C2-symmetry (2, 3),3 which are excellent Lewis base in an organocatalytic process for preparing chiral allylamines. −The enantioselective synthesis of NPS-R-568 (a chiral α-methylbenzylamine with calciomimetic activity) and its trifluoromethyl analogue using the isopropylsulfinamide 4 as inducer of chirality. 4 −The development of an effective methodology for the synthesis of differents biarylsulfoxides (5)5 by asymmetric Suzuki-Miyaura cross-coupling. The modularity of the approach is demonstrated by the preparation of a variety of enantiopure axially chiral mixed S/N and S/P ligands
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35

Schaarschmidt, Dieter. "Über chirale Phosphinoferrocene und deren Anwendung in der (atropselektiven) Synthese räumlich gehinderter Biaryle über eine Suzuki-Miyaura-Reaktion." Doctoral thesis, Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-158105.

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Die vorliegende Dissertation beschäftigt sich mit der Synthese und Charakterisierung drei verschiedener Typen chiraler Phosphinoferrocene sowie deren Anwendung in der Palladiumkatalysierten Suzuki-Miyaura-Reaktion. Der Schwerpunkt liegt dabei auf Untersuchungen zur Synthese räumlich gehinderter Biaryle sowie auf atropselektiven Biarylkupplungen. Über eine Ullmann-artige Kupplung von Iodferrocen mit sekundären Alkoholen wurden zunächst chirale Ferrocenylalkylether synthetisiert, die mit Hilfe dirigierter Lithiierungen in 1,1'-disubstituierte Phosphinoferrocene der Art Fe( 5-C5H4OR)( 5-C5H4-C6H4-2-PR'2) sowie planar-chirale 1,2,1'-trisubstituierte Ferrocene des Typs Fe( 5-C5H3-1-PPh2-2-OR)( 5-C5H4SiMe3) überführt werden konnten. Erstere eignen sich für die Umsetzung räumlich gehinderter Arylhalogenide in der Suzuki-Miyaura-Reaktion, wobei die katalytische Produktivität mit sinkendem Tolman Kegelwinkel der Phosphine steigt. Darüber hinaus ist es möglich, Kupplungsreaktionen zwischen nicht aktivierten Bromaromaten und Phenylboronaäure bei ultraniedriger Katalysatorbeladung (1 ppm) durchzuführen. Die 1,2-P,O-substituierten Ferrocene erlauben die Synthese tri-ortho-substituierter Biaryle. Dabei zeigte sich, dass die Enantioselektivität der Umsetzung hauptsächlich durch die planare Chiralität des Ferrocens und nicht durch den chiralen Alkoxysubstituenten bestimmt wird. Darauf aufbauend wurde eine Serie verschieden substituierter planar-chiraler Phosphinoalkenylferrocene der Art Fe( 5-C5H3-2-PR'2-(E)-CH=CHR)( 5-C5H5) synthetisiert. Die elektrochemische Untersuchung dieser Verbindungen zeigte, dass die -Donoreigenschaften des Phosphins durch die elektronischen Eigenschaften des alkenylgebundenen Substituenten R nicht verändert werden. Dies erlaubt die unabhängige Variation der -Donor-/ -Akzeptoreigenschaften des Phosphins und des Alkens. Abschließend wurde ein Vertreter der Phosphinoalkenylferrocene in der Synthese tri- und tetra-ortho-substituierter Biaryle sowie in atropselektiven Biarylkupplungen eingesetzt. Die Leistungsfähigkeit des Katalysators in der Suzuki-Miyaura-Reaktion wurde durch die Variation der Substratpalette untersucht.
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36

López, Viveros Melissa. "Influence des propriétés d'un réseau polymère sur la synthèse in situ de nanoparticules de palladium : application aux membranes catalytiques de grande efficacité en chimie fine." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30284.

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Des membranes polymères catalytiques ont été préparées via la polymérisation photo-amorcée de monomères acryliques à la surface de membranes support MicroPES(r). Des nanoparticules de palladium (PdNP) avec diamètre moyen compris entre 4 et 10 nm sont ensuite synthétisés et immobilisées dans ces gels polymères greffés. Cette thèse se focalise sur le greffage d'un gel de polymère neutre : (2-hydroxyethyl acrylate) (PHEA), pour négliger les contributions ioniques du réseau polymère sur la synthèse in-situ des PdNP. La stabilisation de PdNP dans le gel de PHEA greffé est possible par des moyens stériques étant donné que la distance entre des chaînes de polymère réticules (entre 0.3 à 2.5 nm) est plus petite que le diamètre moyen de PdNP. Une approche à la fois théorique et expérimentale, sur la base des mecanismes de nucléation et de croissance, permet la conception de PdNP de taille spécifique. La performance catalytique des membranes a été évaluée avec une configuration en filtration traversée. Sur la réaction de couplage de Suzuki-Miyaura, des conversions et sélectivités de 100 % ont été obtenues pour des temps de séjour de 10 secondes avec des membranes planes. Les réactions d'hydrogénation de plusieurs composés aromatiques ont également été testées. Des taux de conversion élevés ont été obtenus en quelques secondes avec des membranes planes en filtration avec des solutions saturés d'H2. Des taux de conversion élevés sont obtenus en seulement quelques minutes avec des membranes fibres creuses catalytiques en mode contacteur permettant une importante intensification du procédé
Catalytic polymeric membranes are prepared via photo-grafting polymerization of neutral acrylic monomers onto the surface of a MicroPES(r) membrane support. Palladium nanoparticles (PdNP) of mean diameter of 4-10 nm are synthetized and immobilized within the grafted polymer gels. The research is focused on grafting a neutral polymer gel: poly (2-hydroxyethyl acrylate) (PHEA), to avoid any ionic contribution of the polymer network on the in-situ synthesis of PdNP. The stabilization of PdNP within the grafted PHEA is achieved by steric means as the distance between polymeric crosslinked chains (ca. 0.3 to 2.5 nm) is smaller than the mean diameter of PdNP. Both theoretical and experimental approaches are presented on the PdNP synthesis as an approach to conceive PdNP of specific sizes using nucleation and growth theories. Catalytic performance of the membranes is evaluated in flow-through configuration. Catalytic tests are performed on Suzuki-Miyaura cross-coupling reactions. Full conversion and selectivity within 10 seconds of residence time using flat sheet membrane are obtained. Hydrogenation of several aromatic compounds are also tested and high conversions were achieved within seconds of residence time using flat sheet membranes in flow-through configuration with H2-saturated solutions and within minutes using catalytic hollow fibers in contactor mode
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37

Ng, Choi I.-teng Montserrat. "Solid-phase synthesis of 5-arylhistidine-containing peptides: from linear antimicrobial peptides to cyclic peptides derived from arylomycins and aciculitins." Doctoral thesis, Universitat de Girona, 2015. http://hdl.handle.net/10803/380739.

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The incorporation of unsymmetrical biaryl systems into peptide sequences is a strategy that can improve their biological activity. Due to the difficulty of arylating the 4(5}-position of the imidazole ring, this doctoral thesis was focused on the development of efficient methodologies for the solid-phase synthesis of 5-arylhistidine-containing antimicrobial undecapeptides through a Suzuki-Miyaura reaction under microwave irradiation. The extension of this protocol allowed the preparation of biaryl cyclic peptides of different ring sizes bearing a His-Phe or His-Tyr biaryl linkage. Then, it was developed a procedure for the total solid-phase synthesis of biaryl cyclic lipopeptides derived from arylomycins. These strategies were extended to the preparation of biaryl cyclic analogues of the marine bicyclic pptides aciculitins. In particular, it was achieved the synthesis of analogues of the northern and the southern hemispheres of aciculitins as well as biaryl bicyclic peptides incorporating a Phe-Phe, a Phe-Tyr, a His-Tyr or a Tyr-Tyr biaryl bridge
La incorporació de sistemes biarílics asimiètrics en seqüències peptídiques es considera un enfocament útil per a millorar l'activitat biològica de pèptids. Tenint en compte la dificultat d'arilar la posició 4 (5) de l'anell d'imidazole, aquesta tesi doctoral es centra en el desenvolupament de noves estratègies eficients per a la preparació en fase sòlida d'undecapèptids antimicrobians contenint una 5-arilhistidina a través d'una reacció de Suzuki-Miyaura sota irradiació microones. L'extensió d'aquesta metodologia ha permès la síntesi de pèptids biarílics cíclics de diferents mides que incorporen un enllaç His-Phe 0 His-Tyr. Posteriorment, s'ha desenvolupat un procediment per la síntesi total en fase sòlida de lipopèptids biarílics cíclics derivats de les arilomicines. Les estratègies anteriors s'han estès a la preparació de compostos biarílics anàlegs dels pèptids bicíclics marins aciculitines. Concretament, s'ha preparat anàlegs dels hemisferis nord i sud de las aciculitines així com pèptids biarílics bicíclics que incorporen un pont Phe-Phe, Phe-Tyr, Tyr-His 0 Tyr-Tyr.
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38

Lassalas, Pierrik. "Étude de nouvelles méthodologies d’arylation directe en séries azole et pyridine : Application à la synthèse de coeurs de thiopeptides antibiotiques de la série d." Thesis, Rouen, INSA, 2012. http://www.theses.fr/2012ISAM0024/document.

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Face à l’apparition grandissante de souches bactériennes multi-résistantes à l’arsenal d’antibiotiques actuels, les thiopeptides antibiotiques, bien que connus depuis plus de 60 ans, suscitent actuellement un fort regain d’intérêt. En effet, cette classe de molécules présente une forte activité antibiotique contre des souches bactériennes résistantes et multirésistantes, et met en œuvre deux modes d’inhibition originaux de la synthèse protéique encore inexploités en thérapie antibiotique humaine. Leur développement pharmacologique est en particulier freiné par la difficulté de préparation de ces molécules très complexes. L'élaboration d'une stratégie innovante de synthèse de la partie la plus complexe de ces molécules, le cœur hétérocyclique est étudiée dans ce travail. Cette approche repose sur l'étude et la valorisation de nouvelles méthodologies de fonctionnalisation directe des liaisons C-H et C-X de mono- et bis-thiazoles avec une large gamme d’hétéroaromatiques. Sa viabilité est démontrée par la préparation du cœur hétérocyclique commun aux amythiamicines
Due to the emergence of multiresistant bacterial strains to standard antibacterial treatments, thiopeptides antibiotics are actually highly considered, though they are known for 60 years. They show an excellent antibiotic activity against multiresistant bacterial strains, and implement two originals inhibition mechanisms of protein synthesis, still unemployed in human therapy. However, the difficulty to prepare these complex macromolecules limits their pharmacological development. The development of a new strategy to synthetize the most complicated part of these macromolecules, their heterocyclic core, is studied here in. This approach is based on the study and the exploitation of novel direct C-H and C-X transition-metal-catalyzed couplings of mono- and bithiazoles units with a broad panel of heteroaromatics. Its viability is here demonstrated trough the multi-step synthesis of the common heterocyclic core of amythiamicins
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39

Damon, Eldon Pierre. "Green synthesis: the use of brown algae in the synthesis of palladium nanoparticles and applications in carbon – carbon bond formation reactions." University of the Western Cape, 2020. http://hdl.handle.net/11394/7721.

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>Magister Scientiae - MSc
Due to the negative impact on the environment and the associated biological risks on human and animal life, the need for eco-friendly synthetic protocols is critical. With the rapid advancement in nanotechnology, this extends to the synthesis of nanomaterials. Eco-friendly nanoparticle synthesis protocols have led to the use of fungi, plants and other biological substances, due to their remarkable ability in reducing metal ions. This led to the formation of very efficient hybrid catalysts, which are partially organic/inorganic composites. Palladium nanoparticles have drawn much interest due to its potential in catalytic applications and in photovoltaic cell development. In this study, the brown marine algae, Ecklonia radiata, was employed as a putative palladium nanoparticle bioreactor. Aqueous extracts of the algae were used as a supporting matrix for the synthesis of palladium nanoparticle (AE-PdNPs) catalysts according to the principles of green chemistry. The catalysts were then assessed for their capability in various carbon-carbon coupling reactions such as Suzuki-Miyaura, Sonogashira, and Heck coupling reactions. Selectivity studies were also performed. The PdNPs were compared to “model” polyvinylpyrrolidone palladium nanoparticles (PVP-PdNPs), synthesized according to literature methods. A variety of spectroscopic techniques were used to characterize the nanoparticles and the organic reaction products, including HRTEM, EDX, NMR, FTIR, DLS, TGA, UV-Vis, ICP-AES, GC-MS and XRD spectroscopy. qNMR was used to determine the product % yields. The aqueous extracts were characterised using NMR and a variety of assays, including total antioxidant potential, total reducing power and radical scavenging ability) to assess its ability to reduce the Pd metal salt. 2D NMR revealed polysaccharides and polyphenols to be the major and minor components, respectively, present in the extract. HRTEM images revealed the average size of the AE-PdNPs and PVP-PdNPs to be 12 nm and 8 nm, respectively. The images also showed the shapes of the NPs to be cubic for the AE-PdNPs and cubic or triangular for the PVP-PdNPs. SAED and XRD spectroscopy revealed the face-centred cubic phase and polycrystalline nature of the AE-PdNPs. No reliable data, other than the HRTEM images was obtained for the PVP-PdNPs. Zeta potential and DLS measurements confirmed the negative charge present on the surface of the nanoparticles, while the hydrodynamic radii were found to be 65 nm and 99 nm for the AE- and PVP-PdNPs, respectively, substantiating the presence of the capping agents. ICP-AES analysis revealed the Pd content of the NPs to be 48.8 and 28.9 ppm for the AE- and PVP-PdNPs. Following characterization, the PdNPs were assessed as potential catalysts in the Suzuki-Miyaura, Heck and Sonogashira carbon-carbon coupling reactions. Bromo and iodo substrates were employed, together with sterically hindered substrates, with a nitro moiety in the ortho or para positions. For the Suzuki-Miyaura reactions, both sets of PdNPs revealed slightly higher yields for the products synthesized using the bromo substrate (>90%), while low yields (40 – 55% yields) were obtained for the ortho substituted substrate in comparison to the para substrate (>90% yields). The Heck coupling reactions with butyl acrylate and 4-iodoacetphenone were successful (~70% yields), while reactions with 4-bromoacetophenone failed. However, the Sonogashira couplings did not proceed at all. With the series of reactions NPs showed some selectivity, with the AE-PdNPs consistently producing higher yields for the products obtained. This may be due to overall nature of the NPs, or due to the higher platinum loading content for the AE-PdNPs.
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40

Cerezo, Frias Vanessa. "Síntesi de base sòlida de pèptids biarílics contenint 5-arilhistidines." Doctoral thesis, Universitat de Girona, 2009. http://hdl.handle.net/10803/8054.

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Els aminoàcids biarílics es troben en una àmplia varietat de pèptids naturals amb important activitat biològica. Concretament, les arilhistidines formen part de les aciculitines, pèptids amb activitat citotòxica i antifúngica, La reacció de Suzuki-Miyaura és el mètode més versàtil per obtenir biarils assimètrics, encara que, fins el moment, no s'havia aplicat per a l'arilació de l'imidazole de la histidina. L'objectiu general d'aquesta tesi fou demostrar que es podia arilar l'imidazole de la histidina en fase sòlida mitjançant una reacció de Suzuki-Miyaura. En primer lloc, es sintetitzaren 4(5)-metil-5(4)-fenilimidazole i 4(5)-metil-5(4)-(2-metoxifenil)imidazole a través de l'acoblament creuat entre un N-benzilbromoimidazole i el corresponent àcid arilborònic. Posteriorment, s'arilaren 5-bromohistidines utilitzant diversos àcids arilborònics mitjançant una reacció de Suzuki-Miyaura assistida per irradiació micrones, tant en dissolució com en fase sòlida. I finalment, mitjançant aquesta metodología, es sintetitzaren pèptids antimicrobians contenint 5-arilhistidines actius contra bacteris gram-negatius responsables d'importants malalties en plantes com el foc bacterià.
Biaryl amino acids are present in a great variety of natural peptides which display important biological activities. In particular, arylhistidines naturally occur in cytotoxic and antifungal marine peptides, aciculitins. The Suzuki-Miyaura cross-coupling is the most versatile method to obtain unsymmetrical biaryls. Up to now, it had not been applied to the arylation of the histidine imidazole ring. The main objective of this thesis was to demonstrate that a Suzuki-Miyaura reaction was amenable to solid-phase arylation of the histidine imidazole ring. Firstly, it was synthesized 4(5)-methyl-5(4)-phenylimidazole and 4(5)-methyl-5(4)-(2-methoxyphenyl)imidazole by cross-coupling between N-benzylbromoimidazole and the corresponding arylboronic acid. Secondly, 5-bromohistidines were arylated with several arylboronic acids by a microwave-assisted Suzuki-Miyaura cross-coupling reaction in solution as well as solid-phase leading to the corresponding arylhistidines. Finally, antimicrobial peptides containing 5-arylhistidines were prepared using the previous methodology. They showed activity against gram-negative bacteria responsible of important plant diseases such as fire blight.
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Aroua, Rahma. "Etudes de complexes organométalliques formés par des calixarènes fonctionnalisés par des carbènes N-hétérocycliques." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF062/document.

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Une série de calixarènes portant une unité imidazolium ou deux, en conformation cône ont été synthétisés et caractérisés par différentes méthodes. Ces sels chargés positivement constituaient des précurseurs de carbènes N-hétérocycliques pour la synthèse de complexes de nickel correspondants. Les complexes Ni-NHC-calix[4]arènes obtenus ont été testés dans la catalyse de la réaction de couplage croisé de Suzuki-Miyaura. Des moyennes à bonnes conversions ont été obtenues selon l’espacement du centre métallique de la cavité calixarénique, ainsi que le nombre de centre métallique présents sur la même plateforme
A series of new calix[4]arenes bearing one or two imidazoliums units in the lower rim were synthesized as precursors of N-heterocyclic carbenes for the synthesis of the corresponding nickel complexes. All products obtained were characterized by NMR spectroscopy, microanalysis and mass spectroscopy and was revealed to be in cone conformation. The application of Ni-NHC-calix[4]arene in Suzuki-Miyaura cross coupling showed moderate to good conversions. This is been depending on the length of the alkyl chain and the number of the catalytic centers grafted on the platform
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42

Lobrégat, Virginie. "Immobilisation d'organobores sur resines ioniques et reaction multi-composants pour la synthese de macrocycles par couplage de suzuki-miyaura." Rennes 1, 2000. http://www.theses.fr/2000REN10063.

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Ce memoire traite de l'immobilisation d'organobores sur des resines ioniques et de l'utilisation de reactions multi-composants pour la synthese de macrocycles par couplage de suzuki-miyaura decrochant. Dans un premier temps, des acides aryl et vinylboroniques ont ete quaternarises et immobilises sur des resines ioniques de type dowex a contre ion hydroxyle, sous la forme de borates effectuant l'etape de transmetallation dans le couplage de suzuki-miyaura. Le greffage peut etre controle par rmn 1 1b et 1 3c dans des conditions standard. Les supports reactifs ont ete engages dans des couplages de suzuki-miyaura en presence de nombreux halogenures d'aryle : la reaction est decrochante et conduit aux biaryls et styrenes attendus avec de tres bonnes conversions. Les conditions experimentales ont ete etudiees et l'eau s'est averee un solvant de choix pour eviter la formation de produit secondaire d'homocouplage. Cette methodologie a ete etendue a la macrocyclisation par couplage biarylique de suzuki-miyaura. Les precurseurs de macrocycles, portant les fonctions acide boronique et halogenure d'aryle necessaires au couplage, ont ete synthetises par une reaction multi-composants. Elle fait intervenir un aldehyde, un isocyanoacetamide et une amine secondaire pour conduire en une seule etape a un oxazole 2,5-disubstitue. La synthese de chacun des partenaires portant les fonctions requises a ete optimisee. La reaction multi-composants a lieu avec une excellente conversion. Les divers precurseurs ont ete immobilises sur une resine ionique par leur fonction acide boronique, et par ce biais purifies. En presence de palladium(0), la macrocyclisation decrochante a lieu, conduisant aux macrocycles qui possedent des motifs biarylique et oxazole avec des rendements de 20 a 25%. En milieu acide, l'oxazole peut etre hydrolyse : on accede alors a un biarylcyclopeptide, dont la structure s'apparente a celle de composes biologiquement actifs.
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43

Korb, Marcus. "Anionic Phospho-Fries Rearrangements for the Synthesis of Planar-Chiral Ferrocenes and their Application in (atropselective) Suzuki-Miyaura Reactions." Doctoral thesis, Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-229081.

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The present PhD thesis describes the synthesis and characterization of novel planarchiral 1,2-P,O-ferrocenes and their application in the Pd-catalyzed Suzuki-Miyaura reaction. It was especially focused on the development of a new synthetic pathway to this type of substitution pattern by applying the anionic phospho-Fries rearrangement in ferrocene chemistry. Starting from hydroxy ferrocene, a high diversity of Fc–O–P- type (Fc = (n5-C5H5)(n5-C5H4)) compounds were synthesized, whereby the electronic properties of the phosphorus fragments were varied. The anionic phospho-Fries rearrangement successfully occurred subsequent to an ortho-lithiation with a non-nucleophilic base giving the 1,2-P,O-ferrocenes in up to quantitative yields. The usage of chiral pool-based alcohols for the synthesis of chiral ferrocenyl phosphates allowed a diastereoselective proceeding, giving single isomers in up to 95% de. Temperature-dependent investigations of mixed ferrocenyl-, phenyl- and Nheterocyclicphosphates revealed a limitation of ferrocenyl-based rearrangements per reaction step, contrary to phenyls. 1,2-P,O-ferrocenyl phosphonates could successfully be converted into phosphines by applying Stelzer P,C cross-coupling reactions on ferrocenes for the first time. Their usage as ligands for C,C cross-coupling reactions was confirmed by the synthesis of sterically hindered biaryls in high yields at 70°C with a low catalyst loading of 1 mol-% Pd. Functionalization of the 1,2-P,O -structural motif could be achieved by applying nucleophilic aromatic substitution reactions (SNAr) as an alternative pathway for the synthesis of ferrocenyl aryl ethers. Subsequent to a Fries rearrangement sterically-demanding 1,3-di-orthosubstituted aryloxy ferrocenes could be obtained. Multi SNAr reactions of hydroxyferrocenes at polyfluorinated arenes gave up to pentaferrocenyl-functionalized aryl ethers, whose electrochemical properties were investigated. The reaction of CH2-enlarged ferrocenylmethanols gave α-ferrocenylcarbenium ions instead of phosphates, while treating them with chlorophosphates. Enantiopure 2-P(S)Ph2-substituted derivatives of these ions underwent a subsequent intermolecular “S2−“ migration, resulting in thioethers, for example (Sp,Sp)-(2-(P(S)Ph2)FcCH2)2S, in a unique mechanism. Instead, the presence of electronrich arenes gave electrophilic aromatic substituted benzenes bearing chiral ferrocenylmethyl backbones. These type of ligands gave biaryls with up to 26 % ee
Die vorliegende Arbeit beschäftigt sich mit der Synthese und Charakterisierung von neuartigen planar-chiralen 1,2-P,O-ferrocenen sowie deren Anwendung in der Pd-katalysierten Suzuki-Miyaura Reaktion. Dabei lag der Focus in der Anwendung anionischer phospho-Fries Verschiebungen auf Ferrocene um dieses spezielle Substitutionsmuster erhalten zu können. Ausgehend von Hydroxyferrocenen wurde so eine Vielzahl neuer Verbindungen des Typs Fc–O–P (Fc = (n5-C5H5)(n5-C5H4)) synthetisiert, wobei die elektronischen Eigenschaften des Phosphor-tragenden Fragmentes variiert wurden. Die anionische phospho-Fries Verschiebung erfolgte im Anschluss einer ortho-Lithiierung mit einer nicht-nucleophilen Base, was 1,2-P,O-Ferrocene nahezu quantitative ergab. Durch die Verwendung von chiral-pool basierten Alkoholen für die Synthese chiraler Ferrocenylphosphate konnte eine diastereoselective 1,3-O->C Umlagerung mit Isomerenreinheiten von bis zu 95 % erreicht werden. Untersuchungen von gemischten Ferrocenyl-, Phenyl- und N-heterocyclischen Phosphaten bei verschiedenen Temperaturen zeigte eine Limitierung Ferrocenyl-basierter Umlagerungen pro Reaktionsschritt im Gegensatz zu denen von Phenylen. Die erhaltenen 1,2-P,O-Ferrocenylphosphate wurden erstmals mittels Stelzer P,C Kreuz-Kupplungsreaktionen erfolgreich in Phosphane umgesetzt. Deren Verwendung als Ligand in C,C Kreuz-Kupplungsreaktionen wurde am Beispiel der Synthese räumlich anspruchsvoller Biaryle in hohen Ausbeuten bei nur 70°C und niedrigen Katalysatorbeladungen von 1 mol-% Pd demonstriert. Die Funktionalisierung des 1,2-P,O-Strukturmotifes konnte durch die Anwendung von nucleophilen aromatischen Substitutionsreaktionen erreicht werden, die einen alternativen Zugang zu Ferrocenylarylethern bietet. Im Anschluss an eine Fries Umlagerung konnten so sterisch anspruchsvolle 1,3-di-ortho-substituierte Ferrocenylarylether erhalten werden. Durch mehrfache SNAr Reaktionen von Hydroxyferrocenen an polyfluorierten Aromaten wurden bis zu fünf-fach substituierte Ether erhalten, deren elektrochemischen Eigenschaften untersucht wurden. Die um eine CH2-Einheit verlängerten Ferrocenylmethanole gaben bei Reaktion mit Chlorophosphaten alpha Ferrocenylcarbeniumionen anstelle der gewünschten Phosphate. Enantiomerenreine 2-P(S)Ph2-substituierte Derivate dieser Ionen durchliefen anschließend einen intermolekularen ”S2–“ Transfer in einem einzigartigen Mechanismus, was bspw. in Thioethern des Typs (Sp,Sp)-(2-(P(S)Ph2)FcCH2)2S resultierte. In Anwesenheit elektronenreicher Aromaten wurden elektrophile aromatischen Substitutuionen und die Bildung chiraler ferrocenylmethyl-substitutuierter Benzene beobachtet. Deren Einsatz als Ligand ergab Biaryle mit bis zu 26 % ee
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44

Riemer, Martin [Verfasser], and Bernd [Akademischer Betreuer] Schmidt. "Vom Phenol zum Naturstoff : Entwicklung nachhaltiger Mikrowellen-vermittelter SUZUKI-MIYAURA-Kupplungen und Tandem-Reaktionen / Martin Riemer ; Betreuer: Bernd Schmidt." Potsdam : Universität Potsdam, 2015. http://d-nb.info/121839840X/34.

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45

Billaud, Célia. "Approche synthétique de la norbadione A : nouvelle préparation d'alcools à partir de sulfones et de dérivés borés." Paris 11, 2005. http://www.theses.fr/2005PA112222.

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L'approche synthétique de la norbadione A, pigment fongique apparenté aux acides pulviniques, a été étudiée. Ce composé a la propriété de complexer le césium et a révélé de remarquables propriétés antioxydantes. La première stratégie basée sur un double couplage de Suzuki-Miyaura entre une naphtolactone possédant deux fonctions borées et deux motifs pulviniques portant une fonction triflate, s'est avérée infructueuse et a montré le caractère désactivant de la lactone. Des modifications visant à inhiber le caractère électro-attracteur de celle-ci ont permis d'obtenir un produit bis(couplé) avec un faible rendement. Une seconde approche, basée sur une cyclisation d'arylacétates d'énols, a alors été étudiée afin de construire les fragments pulviniques en plusieurs étapes. L'étape-clé d'insertion d'un acétate d'alkyle à partir d'un triflate a été réalisée à l'aide d'un couplage palladié. Les essais de cyclisation sur un modèle naphtalénique ont permis d'isoler un adduit mono-cyclisé. Une étude parallèle visant à construire le motif tétronique puis à introduire la double liaison exocyclique selon une méthode développée au laboratoire pour l'obtention d'un dérivé pulvinique iodé a été initiée. Enfin, une nouvelle préparation d'alcools à partir de sulfones et de dérivés borés a été développée. Pour cela, deux réactions connues de la chimie du bore ont été combinées. Il s'agit dans un premier temps de la réaction d'anions de sulfones avec des trialkylboranes et dans un deuxième temps, d'un réarrangement thermique des organoboranes intermédiaires visant à placer l'atome de bore en position terminale. Une nouvelle voie d'accès à des alcools primaires a ainsi été mise au point
The synthetic approach of norbadione A, a pigment from mushrooms related to pulvinic acids, was studied. This compound has the property to complex caesium and has shown an antioxidant activity. The first strategy, based on a double Suzuki-Miyaura coupling between a naphtholactone with two boron functions and two pulvinic moieties with a triflate was unsuccessful and has shown a deactivating effect of the lactone. Modifications aimed to inhibit the electro-attracting character of the lactone permitted to obtain a bis(coupled) product with a poor yield. A second approach based on a the cyclisation of enol arylacetates was studied in order to build the pulvinic moiety in several steps. The important reaction of introduction of an alkylacetate from a triflate was realised by a palladium-mediated coupling. The cyclisation attempts carried out using a naphthalenic compound allowed us to isolate a mono-cyclised product. A parallel study was to first build a tetronic moiety and then to construct the exocyclic double bond by a method developed in the laboratory for the preparation of an iodated pulvinic compound. Finally, a new preparation of alcohols from sulfones and boron compounds was developed. Two known reactions in the chemistry of boron were combined. The first one is the reaction between anions of sulfones and trialkylboranes, the second one is a thermal isomerisation which places the boron atom in a terminal position. A new preparation of primary alcohols was thus carried out
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46

Alrawashdeh, Albara I. S. "From Mono- to Tetraphosphines – A Contribution to the Development of Improved Palladium Based Catalysts for Suzuki- Miyaura Cross Coupling Reaction." Doctoral thesis, Universitätsbibliothek Chemnitz, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-80110.

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Im ersten Teil der Arbeit wird die Synthese neopentyl- und neosilylsubstituierter Phosphane zur Verwendung als Liganden in katalytisch aktiven Palladiumkomplexen beschrieben. Die Aktivität wurde in der Suzuki-Miyaura Kreuzkupplungsreaktion getestet. Während die neosilylsubstituierten Phosphane 2:1 Addukte (5b und 5d) mit geeigneten Palladiumsalzen bilden, welche moderate Katalyseaktivität zeigen, untergehen die neopentylsubstituierten Komplexe schnelle Cyclometalierungsreaktionen in Gegenwart von Basen und bilden die katalytisch wenig aktiven Palladacyclen (6a, 6e, and 6g). Die deaktivierende Cylometallierung konnte durch Darstellung der Palladiumcomplexe ausgehend von Pd(cod)Cl2 in Abwesenheit von Basen vermieden werden. Die erhaltenen 2:1 Phosphaneaddukte zeigten deutlich verbesserte Aktivität. Daraus wurde geschlossen, dass die Cyclomettalierung als Nebenreaktion eine wichtige Deaktiverungsmöglichkeit darstellt, diese Überlegung veranlasste uns Trialkylphosphane mittlerer Größe, mit Substituenten die nur schwer eine Cyclometallierungen eingehen können zu testen. Die Verwendung der Phosphoniumsalze 4h (R = Cy, R‘ = neopentyl) und 4m (R = iPr, R‘ = CH2Cy) führt zu höheren Aktivitäten in der Suzuki-Miyaura Kreuzkupplung, als bestes Katalysatorsystem hat sich die Kombination aus Pd2(dba)3 oder Pd(OAc)2 und entsprechendem Phosphoniumsalz ergeben. Im zweiten Teil dieser Arbeit werden Synthesen zu neuen biphenylbasierten Diphosphanen (70, 71, 76, and 77) vorgestellt. Die Palladiumkomplexe wurden ebenfalls auf ihre Eignung als Katalysatoren in palladiumkatalysierten Suzuki-Miyaura Kreuzkupplungen getestet und zeigen für diese Klasse von Komplexen gute Aktivität. Das Tetraphosphan 82 wurde für die Synthese des zweikernigen Palladium(II)-komplex 83 eingesetzt. Durch die Koordination des D2h-symmetrischen Tetraphosphanes an die Palladiumatome wird die Symmetrie des Moleküls erniedrigt und folglich erhält man den formal D2-symmetrischen Komplex 83
In the first part of this thesis, the synthesis and catalytic activity of neopentyl and neosilyl substituted phosphine palladium complexes is described. The complexes have been tested in the Suzuki-Miyaura cross-coupling reaction. Whereas the neosilyl substituted phosphines form 2:1 adducts (5b and 5d) with Palladium salts which showed moderate activity, the neopentyl complexes quickly undergo cyclometallation in presence of bases to form Palladacycles (6a, 6e, and 6g) which showed only moderate catalytic activity. Cyclometallation could be avoided by the preparation starting from Pd(cod)Cl2 in the absence of bases. The obtained 2:1 phosphine adducts showed superior activity. We concluded that cyclometallation process is an important deactivation pathway, this prompted us to test trialkyl phosphine ligands with medium size but substituents not reliable to cyclometallation. We have been pleased to find that 4h (R = Cy, R‘ = neopentyl) and 4m (R = iPr, R‘ = CH2Cy) showed good activity in the Suzuki-Miyaura cross-coupling reaction. The best results have been obtained by in situ preparation of active catalyst from Pd2(dba)3 or Pd(OAc)2 and the appropriate phosphonium salt. In the second part of this thesis, the first synthesis of a new family of biphenyl based bisphosphine ligands (70, 71, 76, and 77) has been reported. Their palladium complexes were successfully tested as catalyst in the Suzuki cross-coupling reaction. Within the class of bisphosphine based palladium complexes they show good activity in Suzuki-Miyaura cross-coupling reaction. Systematically, was expanded our synthesis strategy and we were able to introduce the first synthesis of a highly symmetric 2,2',6,6'-tetraphosphinobiphenyl. Tetraphosphine 82 was used as ligand in a dinuclear palladium(II) complex 83. Upon complexation the D2h symmetric 2,2’,6,6’-tetraphosphine lead to a chiral D2 symmetric complex 83
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47

Green, Anthony Laine. "The Directed ortho Metalation of pyridine derivatives with in situ boronation and links to the Suzuki-Miyaura cross coupling reaction." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ63310.pdf.

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48

Cai, Xiongwei. "Regiospecific synthesis of alkylphenanthrenes using a combined directed ortho metalation, DoM, (Suzuki-Miyaura cross coupling), directed remote metalation, DreM, methodology." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63276.pdf.

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49

Lu, Zhe. "Nickel-catalyzed Suzuki-Miyaura reactions of unactivated halides with alkyl boranes and planar-chiral borabenzene catalysts for Diels-Alder reactions." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62101.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2010.
Vita. Cataloged from PDF version of thesis.
Includes bibliographical references.
Part I describes the expansion in scope of a nickel-catalyzed coupling reaction of unactivated alkyl bromides and alkyl boranes to include unactivated alkyl chlorides. The new method is adapted for use outside of a glove box and is also found to be applicable not only to the coupling of primary chlorides, but also to the coupling of bromides and iodides, both primary and secondary. ... This coupling reaction of chlorides is further adapted to the of p-chloro aryl alkyl amines. This work constitutes an extension directing groups for the asymmetric Suzuki-Miyaura reactions halides. ... Part II details work towards an asymmetric Diels-Alder reaction between cyclopentadiene and methacrolein catalyzed by a planar-chiral boron Lewis acid. This system exhibits a level of turnover that is unprecedented in reactions mediated by planar chiral boron heterocycles. Computational studies shed light on the nature of the 7tsymmetry interaction between borabenzenes and complexed carbonyl groups. The selectivity of the borabenzene-catalyzed Diels-Alder reaction is also examined.
by Zhe Lu.
Ph.D.
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50

Afonso, Afonso Ana. "Pèptids biarílics a partir de 4-iodofenilalanina o 3-iodotirosina per borilació i reacció de Suzuki-Miyaura en fase sòlida. Avaluació de l'activitat antimicrobiana." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/38882.

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En aquesta tesi doctoral es va estudiar la preparació de pèptids biarílics en fase sòlida. En primer lloc, es varen borilar residus de fenilalanina o tirosina presents a la seqüència peptídica a través d’una reacció de Miyaura. A continuació, es varen arilar els boronats resultants a través d’una reacció de Suzuki-Miyaura sota irradiació de microones, utilitzant diversos halurs d’aril i haloaminoàcids. La metodologia trobada es va estendre a la preparació de pèptids biarílics cíclics. Aquesta aproximació presenta l’avantatge d’evitar la síntesi en dissolució i la purificació del boronoaminoàcid. A més, permet la preparació d’una àmplia diversitat de pèptids biarílics a partir d’un únic boronopèptid. L’avaluació de l’activitat biològica dels pèptids sintetitzats va permetre idenficar seqüències actives enfront dels bacteris Erwinia amylovora, Xanthomonas vesicatoria, i Pseudomonas syringae, que són responsables de malalties greus en plantes d’interès econòmic com pereres i pomeres, i que varen resultar ser molt poc tòxics enfront cèl•lules eucariotes.
The present PhD study was focused on the preparation of biaryl peptides on solid-phase. First, phenylalanine or tyrosine residues were borylated through a Miyaura reaction. Then, the resulting boronates were arylated via a Suzuki-Miyaura reaction under microwave irradiation, using a range of aryl halides and haloamino acids. This methodology was extended to the solid-phase synthesis of biaryl cyclic peptides. This strategy is advantageous because it avoids the synthesis and purification of amino acid boronates in solution. Moreover, it allows the preparation of a large diversity of biaryl peptides from a single boronopeptide intermediate. The evaluation of the biological activity allowed the identification of active sequences against the economically important plant pathogenic bacteria Erwinia amylovora, Xanthomonas vesicatoria, and Pseudomonas syringae, and moreover they were not toxic against eukaryotic cells.
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