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Daku, Kokovi Lawson. "Applications of the Suzuki cross coupling reaction." Thesis, University of Bath, 2003. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425882.
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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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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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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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Hassanzadeh, Nazanin. "Suzuki reactions in novel liquids." Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-106739.
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Non-ionic deep eutectic solvent (ni-DES) possesses various advantages such as good solvation, biodegradability, and non-toxicity which makes it a perfect and environmentally friendly solvent for organic synthesis. A Pd (OAc)2 catalyzed, Suzuki reaction of aryl bromide and N-heteroaryl halide with arylboronic acid in green and novel solvent (ni-DES) is described. In this work, the possibility of using ni-DES and the impact of this solvent on the scope of the reaction is studied. It is illustrated that using the mixture of N-alkyl derivatives of urea and acetamide as a green solvent for Suzuki reaction is achievable even though the desired amount of product was not obtained. However, the high yield in ni-DES can be obtained by choosing 4-bromobenzotrifluoride or 4-bromoanisole as the aryl bromide with arylboronic acid that possess the electron donating groups. Despite that, for getting more yield through Suzuki reaction in ni-DES more studies on optimization are required.
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Elmalem, Einat. "Synthesis of π-conjugated polymers via Suzuki cross-coupling polymerization." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608242.
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Kuvayskaya, Anastasia, and Aleksey Vasiliev. "Use of Suzuki Coupling Reaction for Synthesis of Functionalized Materials." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/162.
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Hybrid materials synthesized by grafting of organic molecules onto silica surface have found numerous applications in chemistry, biochemistry, and chemical engineering. In particular, the functionalization of silica gel can be accomplished by various surface reactions of immobilized boronic acids. Suzuki coupling has been chosen due to several advantages, such as mild reaction conditions, tolerance to the aqueous environment, and high yields of the products. The objective of this work was to determine the most effective reaction conditions for modifying porous hybrid materials with large specific surface areas and high density of surface organoboron reactive sites by various functional groups. Prior to modification by Suzuki coupling, the surface of silica gel was functionalized by phenylboronic acid. Two methods were tested for immobilization of phenylboronic acid: hydrosilylation and thiol-ene coupling. The later radical reaction between surface alkylthiol groups and 4-vinylphenylboronic acid was found more effective. Obtained boronated silica gel was used for further functionalization by various aryl halides. Surface Suzuki coupling reaction was catalyzed by palladium acetate in the presence of cesium carbonate as a base, while dimethylformamide was chosen as a solvent. The coupling reactions proceeded at mild heating under constant sonication. Such ultrasonic irradiation was reported earlier to have an activating effect on Suzuki coupling. The analysis of the obtained products indicated formation of surface biaryl compounds, the highest yields have been obtained in reactions with iodobenzene and bromobenzene. Thus, novel functionalized organic/inorganic hybrid materials were successfully synthesized by surface modification of mesoporous silica gel.
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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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Smith, Paul James. "Palladium catalysed Suzuki cross-coupling reactions in ambient temperature ionic liquids." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405785.
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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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Crepy, Karen Viviane Lucile. "A new asymmetric aryl-aryl coupling reaction and its application to the synthesis of novel liquid crystals." Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327498.
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Todd, Matthew H. "Novel encoding strategies for combinatorial chemistry." Thesis, University of Cambridge, 1998. https://www.repository.cam.ac.uk/handle/1810/272807.
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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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Watts, Nicola Louisa. "Improving the scope and understanding of the Symmetric and Asymmetric Suzuki coupling reaction." Thesis, University of East Anglia, 2012. https://ueaeprints.uea.ac.uk/48116/.
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Investigations into the Symmetric and Asymmetric Suzuki cross-coupling reaction have been described. A new reaction protocol has been developed in which isolated pre-activated sodium trihydroxyarylborate salts were employed as the organoboron coupling partner, resulting in a more convenient and stoichiometrically efficient process. This alternative protocol has been applied to symmetric Suzuki reactions employing simple electron-rich and electron-poor aryl halide partners, and to sterically challenging Suzuki reactions employing bulkier substrates. Asymmetric (atroposelective) Suzuki coupling reactions were also successfully performed using sodium trihydroxyarylborate salts as coupling substrates. The versatility of these species as general organoboron reagents was also demonstrated by their successful application in a rhodium-catalysed 1,4-addition reaction. Experimental studies of asymmetric Suzuki cross-couplings towards axially chiral biaryl products have also been detailed. Model reactions towards configurationally stable biaryl products were found to undergo a successful chiral induction with the use of chiral ferrocenyl ligand (R)-(S)-PPFA 180, with high enantiomeric excesses achieved in some cases. Investigations into the possible influences on the asymmetric induction process exerted by the electronic and steric properties of the coupling partners were carried out, involving repeat asymmetric reactions towards the biaryl product 1-(2’-nitrophenyl)-2-phenylnaphthalene 179. In these reactions, changes to the reacting moiety of the coupling substrates were tested, with an additional reaction carried out involving the reversal of the organic group borne by each substrate.
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Heaner, William. "Indole synthesis: Knoevenagel/Hemetsberger reaction sequence; Suzuki coupling reactions of basic nitrogen containing substrates." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/52171.
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A series of substituted indoles have been synthesized by the sequential reaction of aromatic aldehydes with ethyl azidoacetate in the presence of sodium ethoxide to form the corresponding ethyl α-azido-β-arylacrylates (Knoevenagel process) followed by a solvent mediated thermolysis (Hemetsberger process). The isolated yields of the ethyl α-azido-β-arylacrylates were significantly increased when employing the sacrificial electrophile ethyl trifluoroacetate. 1H NMR and coupled 1H-13C NMR analysis of the ethyl α-azido-β-arylacrylates indicate that the condensation is stereospecific—only the Z-isomer could be detected. Solvent mediated thermal treatment of the meta-substituted ethyl α-azido-β-arylacrylates resulted in the formation of both the 5- and 7- substituted indoles—the 5-regioisomer being slightly favored over the 7-regioisomer. Analogous thermal treatment of (2Z, 2Z’)-diethyl 3,3’-(1,3-phenylene)bis(2-azidoacrylate) and (2Z, 2Z’)-diethyl 3,3’-(1,4-phenylene)bis(2-azidoacrylate) exclusively produced pyrroloindoles, diethyl 1,5-dihydropyrrolo[2,3-f]indole-2,6-dicarboxylate and diethyl 1,5-dihydropyrrolo[2,3-f]indole-2,6-dicarboxylate, respectively. Results are also reported which indicate that the α-azido-β-arylacrylates can be used in the subsequent Hemetsberger indolization process without prior purification.
Organic substrates containing basic nitrogen centers have been problematic in achieving high yields in the Suzuki coupling process. The origin of this issue is attributed to the complexation of the basic nitrogen center with the palladium catalyst. As a consequence, the use of CO₂ at a variety of pressures was evaluated as a reversible protecting/activating reagent for basic nitrogen containing substrates. The following observations and conclusions were reached. (1) The use of small amounts of water significantly improves the rate and yield of Suzuki coupling reactions. (2) In the presence of aqueous CO₂, careful selection of the base is essential due to formation of bicarbonate and the associated decrease in the amount water. K3PO4 was found to be the most effective base in the presence of CO₂. (3) The yield of product in the Suzuki coupling of 4-amino-2-bromopyridine with phenylboronic acid was evaluated as a function of CO₂ pressure. Compared to reactions in the absence of CO₂, the yield of product increased at all pressures of CO₂ (6.8, 17, and 30.6 atm) - from 15% with no CO₂ to 73% with 30.6 atm of CO₂.
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Chang, Weng Kun. "Development of Tandem Reaction for Synthesis of Highly Functionalized Carbocycles." Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:104067.
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Thesis advisor: James P. MorkenThe Suzuki-Miyaura cross-coupling reaction is a common strategy for the formation of a new carbon-carbon bond in organic synthesis. However, intramolecular coupling of allylboron ester and aryl electrophiles has never been reported. Herein, Pd-catalyzed intramolecular cross-coupling of allylboronic pinacol ester and vinyl or aryl bromides is presented. Pt-catalyzed 1,2-diboration of 1,3-dienes give α-chiral bis-allylboronic esters, which can undergo diastereoselective additions to carbonyl electrophiles tethered to vinyl or aryl halides to generate a new allylboronic ester moiety. Under Suzuki coupling conditions, the allylboronic esters moiety and the vinyl bromides in the allylation products can cross-couple in an intramolecular fashion to afford highly substituted four-, five-, and six-membered rings with excellent yields and moderate diastereoselectivity
Thesis (MS) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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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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Ben, Halima Taoufik. "Engaging Esters as Cross-Coupling Electrophiles." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39493.
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Cross-coupling reactions, where a transition metal catalyst facilitates the formation of a new carbon-carbon or carbon-heteroatom bond between two coupling partners, has become one of the most widely used, reliable, and robust family of transformations for the construction of molecules. The Nobel Prize was awarded to pioneers in this field who primarily used aryl iodides, bromides, and triflates as electrophilic coupling partners. The expansion of the reaction scope to non-traditional electrophiles is an ongoing challenge to enable an even greater number of useful products to be made from simple starting materials. The major goal of this thesis research is to improve and expand upon this field by using esters as electrophiles via the activation of the strong C(acyl)−O bond. Esters are particularly robust in comparison to other carboxylic acid derivatives used in cross-coupling reactions. Success on the activation of such inert functional group using catalysis has both fundamental and practical value. By discovering new reaction modes of this abundant functional group, synthetic routes to access novel or industrially important molecules can be improved.
Chapter 1 of this thesis describes a literature overview of what has been accomplished in the field of cross coupling reactions using carboxylic acid derivatives as electrophilic coupling partners.
Chapter 2 discloses the first palladium Suzuki-Miyaura couplings of phenyl esters to produce ketones. The method is efficient and robust, giving good yields of useful products. The reaction is proposed to proceed via an oxidative addition to the strong C(acyl)−O bond of the ester. In contrast to previous efforts in this field that use traditional catalysts such as Pd(PPh3)4, the developed reaction requires use of an electron-rich, bulky N-heterocyclic carbene ligand, which facilitates the strong bond activation.
Furthermore, a palladium-catalyzed cross-coupling between aryl esters and anilines is reported, enabling access to diverse amides. The reaction takes place via a similar activation of the C−O bond by oxidative addition with a Pd−NHC complex, which enables the use of relatively non-nucleophilic anilines that otherwise require stoichiometric activation with strong bases to react.
Chapter 3 discloses a nickel-catalyzed amide bond formation using unactivated and abundant esters. In this transformation, an accessible nickel catalyst can facilitate the activation of diverse aliphatic and aromatic esters to enable direct amide bond formation with amines as nucleophiles. No stoichiometric base, acid, or other activating agent is needed, providing exceptional functional group tolerance and producing only methanol as a by-product. This reaction is of both fundamental and practical importance because it is the first to demonstrate that simple conditions can enable Ni to cleave the C–O bond of an ester to make an oxidative addition product, which can be subsequently coupled with amines. This discovery contrasts industrially-common and wasteful methods that still require stoichiometric activating agents or multistep synthesis.
Chapter 4 describes the evaluation of different types of cross-coupling reactions using methyl esters as electrophilic coupling partner. A high-throughput screening technique has been applied to this project. A combination between specific ligands, known by their efficiency to activate strong C−O bonds, and literature-based conditions has been designed for the chosen transformations. Using this strategy, two promising hits have been obtained using the same NHC ligand: a decarbonylative Suzuki-Miyaura and a decarbonylative borylation reaction.
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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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Paris, Juraj [Verfasser]. "Combination of Suzuki cross-coupling reaction and biocatalysis in one-pot cascade processes / Juraj Paris." Bielefeld : Universitätsbibliothek Bielefeld, 2019. http://d-nb.info/1206592222/34.
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Fodor, Anna. "Heterogeneous metal-catalysed C-C coupling reactions : research and development." Thesis, Poitiers, 2016. http://www.theses.fr/2016POIT2256/document.
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Des nouveaux catalyseurs bimétalliques à base de palladium et de cuivre ont été développés. Deux voies de préparation ont été testées : l'imprégnation successive (TSI) et la co-imprégnation (CI) en utilisant la zéolithe 4Å (4A) et l'oxyde mixte MgAlxOy comme support. Les catalyseurs ont été caractérisés à l'état frais et testés dans la réaction de couplage Suzuki–Miyaura afin de comparer leurs activités, sélectivités et stabilités. L'étude de stabilité nous a montré que le catalyseur Cu-Pd-4A-TSI restait actif pendant six cycles alors que l'activité du catalyseur Cu-Pd-4A-CI diminuait. Sur le support MgAlxOy, le catalyseur CI était stable pendant six cycles contrairement au catalyseur TSI. Nous avons montré que le point clé pour l'obtention d'une bonne activité et stabilité est la présence de la phase active correspondant à l'alliage Cu/Pd 1/1 identifiée grâce à la caractérisation des catalyseurs et ce quelle que soit la méthode de préparation des catalyseurs. Une différence cruciale existe entre les catalyseurs supportés sur MgAlxOy et 4A : le catalyseur Cu–Pd supporté sur MgAlxOy permet de réduire le temps de réaction de moitié pour une même conversion par rapport à Cu-Pd-4A-TSI. De plus, l'utilisation d'un support plus basique permet, dans une certaine mesure, la diminution de la quantité de la base ajoutée durant la réaction. La réaction Petasis-borono Mannich a été aussi effectuée avec succès sur ces catalyseursNew bimetallic palladium/copper catalysts were developed by successive impregnation (TSI) and co-impregnation (CI) on 4Å molecular sieve (4A) and MgAlO mixed oxides supports. The fresh catalysts were characterised and tested in the Suzuki–Miyaura reaction to test their activity, selectivity and stability. It was observed that while the Cu-Pd-4A-TSI catalyst kept its activity during six cycles that of the Cu-Pd-4A-CI dropped. On MgAlO support the catalyst prepared with CI proved to be stable even for six runs contrary to TSI. The active phase of the reaction – namely the Cu–Pd alloy with atomic ratio 1:1 - was determined with the help of catalyst characterisation of the recovered catalysts. This observation confirms that whatever the way of preparation or the support is, the key-point is the presence of Pd-Cu 1:1 particles to enhance the catalytic performances. A crucial difference between the MgAlO and 4A supported catalyst was found in the reaction time necessary for the Suzuki–Miyaura reaction. With the Cu-Pd-MgAl-CI catalyst the reaction time could be reduced to thirty minutes contrary to one hour with Cu-Pd-4A-TSI. Moreover it was concluded that with a more basic support the reduction of the quantity of the base was possible however it brought slightly decreasing yield. The Petasis-borono Mannich reaction was also performed in the presence of each mono-and bimetallic catalysts
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Zhang, Wanying. "A Mechanistic Approach Towards the Discovery of Catalytic Acylation Reactions." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35646.
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The development of new, efficient methods for the formation of carbon-carbon bonds using transition metal catalysis has broad applications in the field of organic chemistry and is the key to efficient chemical synthesis. Many efforts had been made to develop efficient ways to make these linkages particularly with the aid of metals such as Rh, Pd, Ni, Ru and Cu. Our group is primarily focused on exploring how these transition metals can activate typically inert functional groups, paving way to new synthetic routes to construct more complex molecules.
Chapter 1 describes attempts that were conducted to achieve hydroacylation between an aldehyde and a non-conjugated alkene via a metal hydride intermediate. The use of RuHCl(CO)(PPh3)3 proved to be the most efficient catalyst for this transformation thus far. Mechanistic investigations were conducted to explore different possibilities to enable this transformation. This chapter also identifies a new self-aldol domino reaction, which consists of a self-aldol condensation of an aldehyde, followed by oxidation and decarbonylation giving rise to a ketone product. Finally, the use of a simple and direct method to access deuterated aldehydes using RuHCl(CO)(PPh3)3 as a catalyst and D2O as a deuterium source is outlined.
Chapter 2 describes a novel Suzuki-Miyaura system that couples esters and boronic esters to form the corresponding ketone product. It was found that an NHC-based Pd catalyst is crucial in the transformation wherein it activates the C(acyl)-O bond of the ester. It is notable that this transformation takes place with the absence of decarbonylation. Reactivity under water in the presence of surfactants was also discovered. Results in aqueous media were demonstrated to be milder than in organic conditions, while achieving similar yields. This system was also applied to coupling of esters and anilines.
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Ingner, Fredric. "Suzuki coupling of functionalized arylboronic acids to a 2-Amino-5-(4-bromophenyl)-1,3,4-thiadiazole scaffold." Thesis, Uppsala universitet, Institutionen för kemi - BMC, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-247573.
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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. ByersThis 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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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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Mlynarski, Scott Nathan. "Utilizing Terminal Alkenes in Asymmetric Synthesis: Development and Application of Efficient Diboration/Cross-Coupling Cascades." Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:103555.
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Thesis advisor: James P. MorkenThe first highly enantioselective diboration of unfunctionalized terminal alkenes has been developed using a platinum-phosphonite complex. This transformation produces versatile 1,2-bis(boronate)esters that can manipulated chemoselectively to generate a pletheroa of enantioenriched structural motifs. When combined with an appropriate palladium catalyst, the diboration product undergoes an efficient alkyl boron cross-coupling with aryl and vinyl electrophiles producing a wide range of enantioenriched homobenzylic and homoallylic boronates. Alternatively, when the 1,2-bis(boronate)ester diboration product contains an adjacent Z-olefin (derived from diboration of cis-1,3-dienes), allylation to aldehydes can be achieved delivering the syndiastereomer of product exclusively with excellent chirality transfer. Notably, the products obtained from the two described reactions contain an additional boronate moiety, which can be further functionalized through known carbon-boron bond transformations
Thesis (PhD) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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Schäfer, Philipp. "Enantioselective synthesis of chiral building blocks with non-stabilized nucleophiles." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:d69d1861-5368-495a-932d-7e1aa6bc5dfb.
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This thesis describes the combination of non-stabilized nucleophiles and prochiral/racemic electrophiles in transition metal catalyzed asymmetric transformations. These enantioselective reactions have tremendous potential for the formation of chiral building blocks and new structural motifs that can be found in a variety of natural products and their derivatives. The first part of the thesis focuses on the synthetic approach towards anti-cancer active diterpenoid structures. The two key steps involve a Cu-catalyzed asymmetric conjugate addition of alkylzirconocenes to enones and an intramolecular oxidative cyclisation. Particular investigations into the cyclisation are made with organocatalysis, transition metal catalysis and electrochemistry for the formation of these tricyclic scaffolds. In the second part this work builds on the Rh-catalyzed asymmetric Suzuki-Miyaura coupling of benzeneboronic acids and cyclic allyl chlorides, which has been developed in our group. Here, the main point is to use more challenging coupling partners, such as heteroaromatic boronic acids, which are coupled to racemic cyclic allyl halides. The utility of this method is demonstrated by performing further transformations and an asymmetric synthesis of the natural product (+)- isoanabasine. The last chapter describes the development of a new asymmetric Hiyama coupling of arylsiloxanes with racemic cyclic allyl chloride. Attempts are made to generate substrates that are not accessible via the asymmetric Suzuki - Miyaura reaction. After extensive optimisation a variety of arylsiloxanes is generated and tested with the best conditions to prove its utility in comparison to the asymmetric Suzuki-Miyaura coupling.
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Yang, Yuan. "Graphene as a Solid-state Ligand for Palladium Catalyzed Cross-coupling Reactions." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5488.
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Palladium-catalyzed carbon-carbon cross-coupling reactions have emerged a broadly useful, selective and widely applicable method to synthesize pharmaceutical active ingredients. As currently practiced in the pharmaceutical industry, homogeneous Pd catalysts are typically used in cross-coupling reactions. The rational development of heterogeneous catalysts for cross-coupling reactions is critical for overcoming the major drawbacks of homogeneous catalysis including difficulties in the separation, purification, and quality control process in drug production. In order to apply heterogeneous catalysis to flow reactors that may overcome this limitation, the catalyst must be strongly bound to a support, highly stable with respect to leaching, and highly active. While the primary role of supports in catalysis has been to anchor metal particles to prevent sintering and leaching, supports can also activate catalytic processes. In this study, by using a xi combined theoretical and experimental method, we probed the effect of graphene as support in the complex reaction cycle of Suzuki reactions. The density functional theory study provides a fundamental understanding of how a graphene support strongly binds the Pd nanoparticles and act as both an efficient charge donor and acceptor in oxidation and reduction reaction steps. Theoretical investigations prove that the Pd-graphene interaction promotes electron flow between the metal cluster and the defected graphene to reduce reaction barrier. The ability for graphene to both accept and donate charge makes graphene an unusually suitable support for multi-step catalytic processes that involve both oxidation and reduction steps. The computer-aided catalyst design with the atomic precise accuracy demonstrates the Pd/graphene catalyst can be further optimized and the first-row transition metal nanoparticles have great potential to replace Pd to catalyze the Suzuki reaction. The corresponding experimental study shows that the method to immobilize the Pd nanoparticles on the graphene is crucial to increasing the reactivity and stability of the resulted catalyst. A comparison of the activation energy and turn over frequency for a series of supported and homogeneous catalysts indicates that exposing palladium-graphene to defect inducing microwave radiation results in dramatically lower activation energies and higher turnover frequencies. Furthermore, the heterogeneity tests demonstrate the Suzuki reactions are carried out on the surface of the immobilized Pd nanoparticle agreeing with the theoretical results. A method to engineer the 2-D graphene support to a 3-D structure to minimize the re-stacking and agglomeration of the graphene lattice will also be introduced in this study.
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Zhang, Ye. "Development of amide-derived P,O-ligands for Suzuki cross-coupling of aryl chlorides and the asymmetric version /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202005%20ZHANG.
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François, Benjamin. "Utilisation d’organoboranes fonctionnalisés pour la construction de structures polycycliques." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S114.
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Les composés organoborés constituent des outils remarquables en synthèse organique de par leur chimie très diversifiée. Les travaux présentés dans ce mémoire abordent de nouveaux aspects de leur réactivité. Une méthode de synthèse rapide et efficace de 9-hydroxyfluorènes est décrite via une séquence tandem Suzuki/ aldolisation phénolique. Ce processus a été ensuite étendu aux 9-aminofluorènes en ajoutant simplement comme troisième partenaire diverses amines au milieu réactionnel. Des hypothèses mécanistiques sont proposées pour rationaliser ces résultats expérimentaux. Dans une deuxième partie, est présentée une étude articulée autour de la mise en œuvre de réactions ène sur des diènes borylés 1,3. Les produits ainsi obtenus sont ensuite utilisés comme intermédiaires clé de structures polycycliques plus complexes. Enfin, le troisième chapitre est consacré à une nouvelle voie d'accès aux pyrroles C-fusionnés à partir de diènes cycliques borylés, ces derniers étant préparés par hydroboration d'énynes, bora-Wittig ou métathèse. Une grande diversité structurale est alors accessible à partir de ces précurseurs d'accès aiséOrganoboron compounds are remarkable tools in organic synthesis due to their very diversified chemistry. The work presented in this thesis addresses new aspects of their reactivity. A rapid and efficient synthesis of 9-hydroxyfluorenes is described via a tandem Suzuki/phenol aldolisation sequence. This process was then extended to 9-aminofluorenes by simply adding various amines to the reaction medium as the third partner. Mechanistic hypotheses are proposed to rationalize these experimental results. In a second part, was presented a study articulated around the implementation of ene reactions on borylated 1,3-dienes. The products thus obtained are then used as key intermediates of more complex polycyclic scaffolds. Finally, the third chapter is dedicated to a new access to C-fused pyrroles from borylated cyclic dienes, the latter being prepared by hydroboration of enynes, boron-Wittig or metathesis reactions. A great structural diversity is then accessible from these easily prepared precursors
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Check, Casey. "Design, Synthesis and Characterization of Two-Dimensional Polyelectrolytes." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1291397084.
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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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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 83In 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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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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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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Martin, Thibaut. "Etude de nouvelles méthodologies d'hétéroarylation directe de liaison C-Het C-Br en série thiazolique : application à la synthèse de coeurs thiazolylpyridiniques des thiopeptides de la série d." Phd thesis, INSA de Rouen, 2010. http://tel.archives-ouvertes.fr/tel-00577166.
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Face à l'apparition alarmante et continue de résistance massive des bactéries à l'arsenal actuel d'antibiotiques, la recherche de nouveaux agents antibactériens est actuellement un enjeu sociétal de tout premier ordre. Bien que connus depuis plus de 50 ans, les thiopeptides antibiotiques suscitent actuellement un très fort regain d'intérêt de la communauté scientifique internationale en raison de leurs propriétés antibactériennes remarquables, notamment contre les staphylococcus areus résistants à la méthiciline et les enterococci résistants à la vancomycine, impliquées dans de nombreuses infections qui engagent la vie des patients, et qui s'exercent de façon très intéressante selon deux modes d'action d'inhibition de la synthèse protéique originaux et encore inexploités en thérapie antibiotique humaine. Le travail développé s'inscrit dans ce programme international de valorisation pharmacologique qui repose pour une grande part sur le développement d'approches synthétiques rapides et modulables. Le projet a été centré en particulier sur la conception et la mise en oeuvre de nouveaux plans de synthèse des unités centrales di- ou trithiazolylpyridines, appelées coeurs hétérocycliques, communs à de nombreux thiopeptides de la série d et qui représentent les principaux défis synthétiques. Dans le cadre d'un programme de recherche du laboratoire ciblé sur l'étude de nouvelles méthodes de fonctionnalisation directe d'aromatiques et d'hétérocyclique, un premier travail méthodologique d'étude de la fonctionnalisation directe dans deux séries structurellement représentatives, thiazole-4-carboxylate et 2-cétothiazole, a été réalisé. Ainsi, une nouvelle méthodologie originale d'hétéroarylation directe pallado-catalysée régioselective du thiazole-4-carboxylate de tert-butyle avec une large gamme d'halogéno(hétéro)aromatiques a été développée avec succès. Une seconde méthodologie originale d'hétéroarylation directe de 4-bromo-2-cétothiazoles selon une séquence réactionnelle de boroylation pallado-catalysée suivie d'un couplage de Suzuki-Miyaura (BSC) a également été développée. Un second travail a porté sur l'exploitation des deux méthodologies de fonctionnalisation directe en série thiazolique développées et associées à la méthodologie de construction thiazolique de Hantzsch pour proposer et mettre en oeuvre un nouveau plan de synthèse expéditif et général d'accès aux coeurs hétérocycliques communs à une grande majorité des thiopeptides de la série d basé sur la fonctionnalisation séquencée d'un précurseur pyridinique aisément accessible. En particulier, la stratégie envisagée a permis, à partir des esters 5-bromopicolinates, la préparation tout d'abord d'un analogue thiazolique du coeur hétérocyclique des sulfomycines puis celle des coeurs hétérocycliques des micrococcines et des amithiamicynes.
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Vuoti, S. (Sauli). "Syntheses and catalytic properties of palladium (II) complexes of various new aryl and aryl alkyl phosphane ligands." Doctoral thesis, University of Oulu, 2007. http://urn.fi/urn:isbn:9789514286483.
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Abstract
Thirty three aryl and aryl alkyl phosphane ligands were prepared and characterized for catalytic purposes. The aryl groups in both types of ligands were modified with alkyl substituents (methyl, ethyl, isopropyl, cyclohexyl, phenyl) or hetero substituents (methoxy, N,N-dimethylaniline, thiomethyl). The alkyl groups directly attached to the phosphorous atom were ethyl, isopropyl or cyclohexyl. Mono- and in some cases also dinuclear palladium (II) complexes of the ligands were prepared and characterized. The syntheses of the palladium complexes are solvent-dependent and afford either mono- or dinuclear complexes depending on the choice of the solvent. Additionally, two 2-mercaptobenzothiazole palladium complexes were synthesized and characterized. A rare distorted lantern-type structure was presented for the first time.
The ligands were characterized by 1H, 13C, 31P NMR spectroscopy and mass spectrometry. The palladium complexes were characterized by 31P NMR spectroscopy, X-ray crystallography and elemental analysis. Links between the NMR data of the palladium complexes and ligands and their catalytic activity was screened and correlation found. The crystal structures of the palladium complexes were studied for possible attractive interactions between two ligands. Such interactions were found from two examples. There is an attractive interaction between the phenyl and quinolinyl moieties of 2-quinolinyldiphenyl phosphane. A similar interaction was found between the methyl substitute and phenyl ring of o-tolylphosphane.
The ligands and palladium complexes presented in this thesis were prepared in hope of finding suitable catalysts for Suzuki coupling reactions of various bulky aryl halides and phenyl boronic acids to prepare sterically hindered bi- and triaryls under microwave irradiation. A selection of aryl alkyl phosphane ligands catalyzed the couplings of bulky aryl bromides and even unactivated aryl chlorides efficiently and produced high yields. The reaction conditions of a new catalyst system were optimized, and it was noticed that the addition of a small amount of water enhanced the purity and yield of the coupling products further.
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Walczak, Matthew C. "Total Synthesis Of Polyene Natural Products Lucilactaene And Gymnoconjugatin: Development Of A Boron-Tin Linchpin." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1206036742.
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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 préparésThe 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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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 hormonaleNanotechnology 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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Amorim, Ana Catarina de Melo. "Desenvolvimento de métodos catalíticos para a síntese de compostos heterocíclicos biológicamente ativos." Master's thesis, Universidade de Évora, 2019. http://hdl.handle.net/10174/26548.
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Esta dissertação centra-se na síntese de compostos heterocíclicos aromáticos tricíclicos, que contêm átomos de nitrogénio, nomeadamente as fenantridinas e as dibenzodiazepinas (DBDAs), as quais apresentam um largo espetro de atividades biológicas.
Uma família de fenantridinas foi sintetizada com sucesso, através da sequência reacional de acoplamento cruzado de Suzuki-Miyaura/condensação carbonílica, partindo de ésteres amino-arilborónicos e de 2-bromobenzaldeídos, 2-clorobenzaldeídos e acetofenonas. Foi também estudada uma via para a síntese destes compostos, utilizando iminas como material de partida.
As estratégias utilizadas para a síntese de DBDAs englobaram o acoplamento de Buchwald-Hartwig, o acoplamento de Chan-Lam, bem como reações de condensação carbonílica, sendo que várias condições foram estudadas.
A inibição das colinesterases (ChE) tornou-se no principal alvo terapêutico para o combate da doença de Alzheimer, pelo que, neste trabalho, foram também estudadas as atividades anticolinesterásicas de alguns dos compostos sintetizados; Development of Catalytic Methods for the Synthesis of Biologically Active Heterocyclic Compounds
Abstract:
This dissertation focuses on the synthesis of tricyclic aromatic heterocyclic compounds containing nitrogen atoms, namely phenanthridines and dibenzodiazepines (DBDAs), which have a broad spectrum of biological activities.
A family of phenanthridines was successfully synthesized through the Suzuki-Miyaura cross-coupling/carbonyl condensation reaction sequence starting from amino-arylboronic esters and 2-bromobenzaldehydes, 2-chlorobenzaldehydes and acetophenones. A pathway for the synthesis of these compounds was also studied using imines as starting material.
The strategies used for the synthesis of DBDAs included the Buchwald-Hartwig coupling, the Chan-Lam coupling, as well as carbonyl condensation reactions, and several conditions were studied.
Inhibition of cholinesterases (ChE) has become the main therapeutic target for the fight against Alzheimer's disease. Therefore, in this work, the anticholinesterase activities of some of the synthesized compounds were also studied.
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Yin, Chunfeng. "Regiospecific synthesis of chlorodihydroxybiphenyls and synthesis of 3,3'-bisaryl substituted BINOLs by combined directed ortho metalation (DoM) and Suzuki-Miyaura cross coupling." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63395.pdf.
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Bortolotto, Tanize. "Síntese nanoparticulas metálicas estabilizadas por copolímeros em bloco com aplicação em reação de redução e acoplamento de Suzuki." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/10576.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe catalytic activity of hierarchical hybrid structures, formed by metal nanoparticles, M-NPs (AuNPs and PdNPs), synthesized and stabilized by block copolymers, is reported in this present work. The catalytic activity was investigated by the study of nanoparticle size and chemical nature of the block copolymer overlaying the M-NP. To evaluate the chemical structure effect of the polymer on catalytic properties of the hybrid systems, a series of eight distinct polymers was used: poly(ethylene oxide)113-b-poly(glycerol monomethacrylate)30-b-poly [2-(diisopropylamino)ethyl methacrylate]50 (PEO113-b-PG2MA30-b-PDPA50), poly(ethylene oxide)113-b-poly[2-(diethylamino)ethyl methacrylate]50 (PEO113-b-PDEA50) , poly(2- methacryloyloxyethyl phosphorylcholine)30-b- poly(2-(diisopropylamino) ethyl methacrylate)60 (PMPC30-b-PDPA60), poly(ethylene oxide)100-b-poly(propylene oxide)65-b-poly(ethylene oxide)100 (PEO100-b-PPO65-b-PEO100 or F127), α-carboxylic ω-thiol poly(N-isopropyl acrylamide)137 (HS-PNIPAM137-COOH), poly(4-vinylpyridine)137-b-(ethylene oxide)45 (PEO45-b-P4VP137), poly(N-vinyl caprolactam)94 (PNVCL94) and poly(N-vinyl caprolactam)53 (PNVCL53). The size of M-NPs was determined by dynamic light scattering (DLS) and their morphology was confirmed by transmission electron microscopy (TEM). Subsequently, was tested the catalyst efficiency, by the reduction of p-nitrophenol to p-aminophenol, the catalyst could be regenerated about 6 times, proving that system (AuNPs and PdNPs) as capacity for regeneration and can be an effective catalyst. The PdNPs were tested like catalyst in reactions of Suzuki coupling.
A atividade catalítica de estruturas hierárquicas híbridas formadas por nanopartículas metálicas, M-NPs (AuNPs e PdNPs), sintetizadas e estabilizadas por copolímeros em bloco é relatada neste trabalho. A atividade catalítica foi investigada em função da natureza química do copolímero em bloco que as revestem. Uma série de 08 (oito) polímeros estruturalmente relacionados foi utilizada: poli(óxido de etileno)113-b-poli(metacrilato de 2,3-diidroxipropila)30-b-poli(metacrilato de 2-(diisopropilamino)etila)50 (PEO113-b-PG2MA30-b-PDPA50), Poli(óxido de etileno)113-poli [ metacrilato de 2-(dietilamino)etil]50 (PEO113-b-PDEA50), poli(2-metacriloiloxietil fosforilcolina)30-b-poli[metacrilato de 2-(diisopropilamino)etil]60 (PMPC30-b-PDPA60), poli(óxido de etileno)100-b-poli(óxido de propileno)65-b-poli(óxido de etileno)100 (PEO100-b-PPO55-b-PEO100 ou F127), α-tiol-ω-ácido carboxílico poli(N-isopropil acrilamida)113 (HS-PNIPAM113-COOH), poli(oxido de etileno)137-b- poli(4-vinil piridina)45 (PEO137-b-P4VP43) poli(N-vinil caprolactana)94 (PNVCL94) e poli(N-vinil caprolactana)53 (PNVCL53). O tamanho das M-NPs foi determinado por espalhamento de luz (DLS) e sua morfologia comprovada através de análise de microscopia de transmissão (TEM). Sua eficiência foi posteriormente testada na catálise da redução do p-nitrofenol a p-aminofenol. Comprovou-se, mediante á ciclos reacionais, que ambos os sistemas (AuNPs e PdNPs) apresentaram capacidade de regeneração, sendo regenerado 6 vezes, provando ser um catalisador eficiente. As PdNPs foram testadas em reações de acoplamento de Suzuki.
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Karakus, Melike. "Electrochemical And Optical Properties Of Solution Processable Benzotriazole And Benzothiadiazole Containing Copolymers." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613562/index.pdf.
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2-Dodecyl benzotriazole (BTz) and benzothiadiazole (BTd) containing copolymers poly(4-(2-dodecyl-2H-benzo[d][1,2,3]triazol-4-yl)benzo[c][1,2,5]thiadiazole (P1), poly(4-(5-(2-dodecyl-7-(thiophen-2yl)-2H-benzo[d][1,2,3]triazol-4-yl)thiophen-2-yl)benzo[c][1,2,5] thiadiazole (P2) and poly(4-(5-(2-dodecyl-7-(4-hexylthiophen-2-yl)-2H-benzo[d] [1,2,3]triazol-4-yl) -3-hexylthiophen-2-yl) benzo[c][1,2,5] thiadiazole (P3) were synthesized via Suzuki polymerization. Electrochemical and optical properties of the polymers were analyzed. The fabrication of solar cells were carried out and current density-voltage (J-V) and incident photon to charge carrier efficiency (IPCE) measurements were done to characterize the solar cells.
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Onuska, Nicholas Paul Ralph. "Studies Towards the Synthesis of 2,5-Disubstituted-3-Fluorothiophenes Using a Directed Ortho-Metalation/Nickel-Catalyzed Cross-Coupling Approach." Kent State University Honors College / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ksuhonors1460652408.
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Nagaradja, Elisabeth. "Bases bimétalliques fer-lithium et zinc-lithium pour la fonctionnalisation (hétéro)aromatique : étude comparative et applications en série azolique." Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S177/document.
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Le but principal de ce travail a été de mettre en évidence le potentiel synthétique de nouvelles bases mixtes fer-lithium dans des réactions de déprotométallation en série aromatique. Dans un premier chapitre, les travaux de la littérature sur les composés fer-métal alcalin et notamment les bases ont d’abord été exposés. Notre étude a permis d’optimiser une nouvelle base fer-lithium et a montré la capacité de celle-ci à réaliser des réactions de déprotonation relativement chimiosélectives et efficaces. Les paramètres de la réaction de déprotométallation ont été optimisés en utilisant l’iode comme électrophile. Cette méthode a été étendue à divers hétérocycles et le piégeage subséquent à différents électrophiles. Dans un second chapitre, le comportement de la base fer-lithium développée a été comparé à celui d’autres bases bimétalliques utilisées au laboratoire. La fonctionnalisation des triazoles par ces bases a montré que la base zinc-lithium était la base la plus appropriée pour ce type de substrats. La fonctionnalisation à l’aide de cette base a donc été étendue en série indazole et benzotriazole. Les résultats ont été rationalisés en utilisant les acidités des hydrogènes des substrats (pKₐ). Dans un dernier chapitre, les méthodes développées ont été valorisées par la synthèse de 2,4-diaryl-1,2,3-triazoles analogues du resvératrol. Les propriétés cytotoxiques de ces molécules seront évaluées. Cette application reste à approfondirThe main purpose of this work was to highlight the synthetic potential of new mixed iron-lithium bases in aromatic deprotometallation reactions. In the first chapter, literature works about iron-alkali metal compounds and notably bases were firstly presented. Our study led to the optimization of a new iron-lithium base and showed its ability to achieve rather chemoselective and efficient deprotonation reactions. The reaction parameters of deprotometallation were optimized by using iodine as the electrophile. This method was extended to various heterocycles and the subsequent trapping to different electrophiles. In a second chapter, the behaviour of the iron-lithium base developed was compared with that of other bimetallic bases used in th laboratory. The functionalization of triazoles using these bases showed that the zinc-lithium was the most suitable base for this kind of substrate. Thus, the functionalization using this base was extended to indazole and benzotriazole series. The results were rationalized by using the hydrogen acidities of the substrates (pKₐ). In the last chapter, the methods developed were made more attractive by the synthesis of 2,4-diaryl-1,2,3-triazoles analogues of resveratrol. The cytotoxic properties of these molecules will be evaluated. This application remains to be explored
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Delaunay, Thierry. "Synthèses concises de pyrazoles et pyridones diversement fonctionnalisées dans le but d’effectuer des réactions de couplages croisés sélectifs." Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10274/document.
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Ce mémoire est subdivise en deux parties. La première partie concerne la synthèse de pyrazoles présentant un intérêt sur le plan agrochimique. En effet, le noyau pyrazole est présent dans de nombreux composes ayant des activités biologiques diverses et en particulier antifongique. Au cours de ce travail, nous avons développé diverses approches convergentes de pyrazoles diversement substitués au moyen de réactions de couplages croisés pallado-catalyses sélectifs et séquentiels à partir de pyrazoles possédant différents points d’encrages. Dans la deuxième partie, nous nous sommes intéressés à la synthèse de diverses furopyridones en tant qu’analogues de produits naturels possédant une activité antifongique, et notamment le Cladobotryal. Dans ce but, diverses alcynylpyridones ont été synthétisées et mises en jeu dans divers processus de cyclisation pour atteindre de manière divergente une série de furo[3,2-c]pyridin-4-ones, furo[3,2-c]pyridin-6-ones et furo[2,3-b]pyridin-4-onesThis thesis is subdivided into two principal parts. The first part is focussed on the synthesis of pyrazole derivatives of agrochemical relevance. Indeed, the pyrazole nucleus is found in numerous compounds possessing interesting biological properties, and notably antifungal activities. Various convergent approaches to diversely substituted pyrazoles have therefore been developed by means of site-selective palladium-catalyzed cross-coupling reactions conducted sequentially on pyrazole scaffolds. In the second part, we have been involved in the synthesis of furopyridones as simplified analogues of natural compounds possessing antifungal activities such as Cladobotryal. Toward this end, various alkynylpyridones have been synthesizes and involved in diverse cyclization processes to access a series of furo[3,2-c]pyridin-4-ones, furo[3,2-c]pyridin-6-ones, and furo[2,3-b]pyridin-4-ones
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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 amythiamicinesDue 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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Brinkley, Kendra W. "The Synthesis of Solid Supported Palladium Nanoparticles: Effective Catalysts for Batch and Continuous Cross Coupling Reactions." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3959.
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Catalysis is one of the pillars of the chemical industry. While the use of catalyst is typically recognized in the automobile industry, their impact is more widespread as; catalysts are used in the synthesis of 80% of the US commercial chemicals. Despite the improved selectivity provided by catalyst, process inefficiencies still threaten the sustainability of a number of synthesis methods, especially in the pharmaceutical industry. Recyclable solid supported catalysts offer a unique opportunity to address these inefficiencies. Such systems coupled with continuous synthesis techniques, have the potential to significantly reduce the waste to desired product ratio (E-factor) of the production techniques. This research focuses developing sustainable processes to synthesize organic molecules by using continuous synthesis methods. In doing so, solid supported metal catalyst systems were identified, developed, and implemented to assist in the formation of carbon-carbon bonds. Newly developed systems, which utilized metal nanoparticles, showed reactivity and recyclability, comparable to commercially available catalyst.
Nanoparticles are emerging as useful materials in a wide variety of applications including catalysis. These applications include pharmaceutical processes by which complex and useful organic molecules can be prepared. As such, an effective and scalable synthesis method is required for the preparation of nanoparticle catalysts with significant control of the particle size, uniform dispersion, and even distribution of nanoparticles when deposited on the surface of a solid support. This project describes the production of palladium nanoparticles on a variety of solid supports and the evaluation of these nanoparticles for cross coupling reactions.
This report highlights novel synthesis techniques used in the formation of palladium nanoparticles using traditional batch reactions. The procedures developed for the batch formation of palladium nanoparticles on different solid supports, such as graphene and carbon nanotubes, are initially described. The major drawbacks of these methods are discussed, including limited scalability, variation of nanoparticle characteristics from batch to batch, and technical challenges associated with efficient heating of samples.
Furthermore, the necessary conditions and critical parameters to convert the batch synthesis of solid supported palladium nanoparticles to a continuous flow process are presented. This strategy not only alleviates the challenges associated with the robust preparation of the material and the limitations of scalability, but also showcases a new continuous reactor capable of efficient and direct heating of the reaction mixture under microwave irradiation. This strategy was further used in the synthesis of zinc oxide nanoparticles. Particles synthesized using this strategy as well as traditional synthesis methods, were evaluated in the context industrially relevant applications.
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White, James Robert. "Transition metal catalysis for novel syntheses and applications of arylboronic acids and their derivatives." Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.577146.
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The research investigations presented herein are concerned with the syntheses and applications of arylboronic acids and their derivatives; with a particular focus on their accessibility or utility in certain of the most significant modern transition metal-catalysed reactions to involve organoborons. Chapter 1 provides an introduction to the field of organoboron chemistry, from its roots employing borane and related highly reactive derivatives for uncatalysed hydroboration of olefins and acetylenes, to the modern classes of organoboron reagents of the greatest significance to the related contemporary transition metal-catalysed methodologies. Furthermore particular emphasis is placed on the discussion of arylboronic acids, their synthesis, and application to transition metal catalysis as a result of their propensity to undergo useful transmetallation events. Chapter 2 details the use of a commercially available sulfonated monophosphine ligand in the rhodium-catalysed 1,2-addition reaction employing aryl aldehydes and arylboronic acids in aqueous media. The high and continued activity of the catalytic complex is demonstrated by it being successfully recycled five consecutive times in the arylation reaction of an aryl aldehyde; as well as being active for the arylations of more sterically demanding aryl methyl ketone substrates. Chapter 3 details the design and synthesis of a novel bench-stable azidomethylene substituted arylboronate ester. The reactivity of this compound and a related analogue in both the coppercatalysed azide alkyne cycloaddition reaction and the Suzuki coupling reaction are detailed, culminating in the proof-of-concept use of such versatile synthetic building blocks in the synthesis of a drug-substance derivative. Chapter 4 details alternative synthetic approaches to that used in Chapter 3 in order to access bifunctional azidomethylene substituted arylboronate esters. In particular the application of Miyaura borylation of arylhalides bearing benzylic azides is addressed as a means to rapidly access substrates which are otherwise shown to be incompatible with classical s-block synthetic intermediates.