Dissertations / Theses on the topic 'Friedel Crafts alkylation'
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Burguin, Emilie. "Zirconia based solid acids for Friedel-Crafts alkylation reactions." Thesis, University of York, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420266.
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Gonçalves, de Almeida José Luis. "Alkylation du benzène par le 1-dodécène sur catalyseurs zéolithiques." Lyon 1, 1994. http://www.theses.fr/1994LYO10292.
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L'alkylation du benzene par le 1-dodecene pour la production des alkylbenzenes lineaires-lab, matiere premiere pour la fabrication de detergent biodegradable, a ete etudiee sur des catalyseurs zeolithiques (h-zsm-5, h-zsm-12, h-y et h-modernites), en vue de leur possible utilisation industrielle, en remplacement des catalyseurs homogenes hf, alcl#3, h#2so#4. Dans ce travail, il a ete analysee l'effet de la force et de la concentration des sites acides sur l'activite et la selectivite dans la formation de lab et de l'isomere 2-phenyl dodecane. Il a egalement ete analysee, comment la variation des proprietes structurales peuvent affecter la diffusion et la distribution des produits du lab. Il a ete mis en evidence que les caracteristiques structurales des zeolithes h-zsm-5, h-zsm-12 et h-y desaluminee jouent un role predominant par rapport aux seules caracteristiques acides et determinant sur l'activite et la selectivite. En ce qui concerne la zeolithe y, malgre la constatation que la force des sites acides augmente avec le taux de desalumination, l'activite de la reaction d'alkylation du benzene par le 1-dodecene croit proportionnellement au nombre de sites acides. La zeolithe y n'exhibe pas des effets de selectivite de forme. Pour les mordenites, l'effet decisive pour la formation des phenyl dodecanes provient de la creation d'une mesoporosite par le processus de desalumination. La presence presque exclusive des 2- et 3-phenyl dodecane, les isomeres les moins encombres, est attribuee a la selectivite de forme envers l'etat de transition ou envers les produits
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POIRIER, JEAN-LUC. "Alkylation de l'isobutane par l'ethylene en presence de catalyseurs solides de friedel-crafts." Caen, 1994. http://www.theses.fr/1994CAEN2037.
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La reaction d'un melange d'isobutane et d'ethylene maintenu liquide a ete etudiee en presence de diverses alumines chlorees. L'influence des parametres de reaction, temperature, dilution, temps de passage a ete examinee. L'alkylat contient uniquement des alcanes. Le catalyseur initialement tres actif se desactive ensuite progressivement. A une temperature proche de 0c et a dilution elevee en ethylene, les hexanes sont les produits majoritaires, le complement etant constitue essentiellement des octanes. La selectivite pour les paraffines branchees est elevee. La reaction de monoalkylation est preponderante et conduit au 2,3-dimethylbutane. Des trimethylpentanes et dimethylhexanes sont obtenus en quantites equivalentes par alkylations successives. Cette selectivite particuliere amene a proposer un nouveau mecanisme par ion carbonium cyclopropanique. Favorisee par l'elevation de la temperature de reaction et une forte concentration en ethylene, l'oligomerisation qui est a l'origine des alcanes superieurs peut etre preponderante sur catalyseur vieilli et sur certains catalyseurs. Les sites acides forts necessaires a la reaction d'alkylation isomerisent les produits primaires d'alkylation et craquent les alcanes superieurs. L'oligomerisation necessite une force des sites moindre que l'alkylation. Une caracteristique essentielle du catalyseur alumine chloree est sa capacite a induire le transfert d'hydrogene
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Laouadi, Ornella Laura Nathalie. "Enantioselective Friedel-Crafts reaction catalysed by alginate aerogels." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18622/.
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Alginates are polysaccharides derived from brown algae, available in nearly unlimited amounts at very low prices. In the presence of some divalent metals, these renewable biopolymers can readily form hydrogels, solvogels and aerogels, characterized by high surface areas, good mechanical properties, tolerance to different media, and easy manageability. For these reasons, alginates are nowadays being thoroughly studied in heterogeneous catalysis; several applications in supported metal catalysis and as heterogeneous Brønsted acids have emerged. However, none of these studies has given an answer to the following intriguing question: can we use the intrinsic chirality of alginates to induce enantioselectivity in a chemical reaction? In order to answer this question a representative reaction, the Friedel-Crafts alkylation of nitroalkenes with indoles, was tested in this master thesis. This study, which involved a large screening of a variety of alginate gels under different reaction conditions, showed that Cu2+ and Ba2+ are the best cross-linking metals to promote the Friedel-Crafts reaction. Indeed, good activity with moderate enantiomeric excesses were obtained under the optimized reaction conditions. Furthermore, these two metals allowed the access to both enantiomers of the products, an important aspect given that only one enantiomeric form of alginates is available. Finally, the heterogeneous nature of the catalysis by one of the two gels was proved, and a good recyclability was demonstrated, by showing that the same catalyst can be used at least five times with similar results.
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Smutek, Bernhard. "Réactions Organiques des Alcools en Conditions Hydrothermales." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20180.
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Cette thèse a pour objectif d'étudier les réactions des alcools en conditions hydrothermales. Dans une phase préliminaire, le phényl-éthanediol a été étudiés. Après aldolisation, cyclisation intramoléculaire et aromatisation sont suivi en formant 1-phénylnaphthalène. L'aldolisation et la cyclisation du type de Friedel et Crafts ont été mise en œuvre.Les transformations de l'éthylène glycol et du 1,2-propanediol sont fortement dépendantes des conditions de réaction (température, durée de réaction et nature du solvant). La réaction de transformation du 1,2-propanediol permet de synthètiser les composés suivants : mésitylène, 2-méthyl-pentènal et 2-éthyl-3,5-diméthyl-cyclopent-2-ènone. Ces produits peuvent être utilisés comme biocarburant ou solvant ou peuvent constituer des matières premières pour des synthèses organiques.Les alkylations du naphthalène et du phénol ont été étudiées en détails en fonction de la nature du solvant. L'emploi d'acide chlorhydrique en concentration de 0.05mol/L à 180°C permet l'alkylation des aromats par l'alcool benzylique. D'autres solvants (acide acétique, acide formique à 1mol/L) permettent d'obtenir ces composés avec des rendements d'alkylation inférieurs. Par ailleurs, le recyclage de ces solvants est réalisable. Notons enfin que l'alcool benzylique peut polymériser et cette polymérisation est fortement influencée par la température utilisée. La polymérisation de l'alcool benzylique a été appliquée avec succès à la séparation des platinoïdes d'une solution modèle d'effluents issue du traitement du combustible nucléaireThis thesis aims to study and to apply reactions of alcohols under hydrothermal conditions.Studies on 1-phenyl-ethanediol show an aldolisation, followed by an intramolecular Friedel-Crafts type reaction and an aromatisation. Finally, it ends up by as 1-phenyl-naphthalene.Ethylene glycol reacts on itself with a strong dependence on the temperature and the solvent. The conversion of 1,2-propanediol showed similar dependences and obtained even the aromatic compound mesitylene and especially the amount of products proves dependence on the temperature and the duration of the reaction. The main compounds can be used as solvents, as biofuel and for syntheses, whereas the byproducts might be biocarburants after hydrogenation.The Friedel-Crafts type reaction is transferred to an intermolecular one. Naphthalene and phenol are studied in more detail. 0.05mol/L HCl are enough in order to benzylate an aromatic compound at 180°C. HCl can be replaced by acetic acid or formic acid, but even concentrations of 1.0mol/L do not achieve results as good as 0.05mol/L HCl. The recycling of the aqueous phase of these reactions is advantageous. Additionally, benzyl alcohol alkylates benzyl alcohol and thus it can polymerize. Higher temperatures lead to longer polymers. This polymerization can be used in the domain of nuclear fuel recycling in order to separate platinum group metals out of a model solution
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Drouillard, Joe͏̈lle. "Utilisation de zéolithes dans les réactions de type Friedel-Crafts : acylation et alkylation du thiophène." Poitiers, 1995. http://www.theses.fr/1995POIT2266.
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Les derives du thiophene ont trouve ces dernieres annees de nombreux debouches dans les domaines alimentaires, agrochimique et surtout pharmaceutique. En particulier, la decouverte des proprietes anti-inflammatoires et antalgiques de certains derives aroyles des acides thienylacetiques a initie de nombreuses recherches concernant les derives du thiophene, permettant de mettre a jour l'activite therapeutique d'autres molecules. L'acylation et l'alkylation des composes aromatiques heterocycliques sont traditionnellement realisees par des reactions de type friedel et crafts, par catalyse homogene au moyen d'acides de lewis ou d'acides protoniques forts. L'utilisation de ce type de catalyseur pose des problemes a la fois d'ordre economique et environnemental. L'objectif de ce travail etait d'essayer de les remplacer par des catalyseurs non polluants et regenerables, comme les catalyseurs acides solides, en particulier les zeolithes. Les resultats obtenus en acylation et en alkylation du thiophene montrent que les performances en terme d'activite et de selectivite des zeolithes sont semblables voire superieures a celles acides de lewis. De plus ces catalyseurs sont parfaitement regenerables, et la recuperation des produits est tres facile. Une etude cinetique complete des deux reactions realisee sur une zeolithe y d'acidite moyenne nous a permis de determiner les mecanismes reactionnels. Nous avons ensuite examine l'influence de la nature du catalyseur sur son activite et sa selectivite, en faisant varier l'acidite et/ou la porosite. L'ensemble des resultats obtenus montre que de nombreux parametres, tels que la temperature, la nature de l'agent acylant ou alkylant, la nature du solvant, l'acidite et la porosite du catalyseur influent sur les vitesses des reactions d'alkylation et d'acylation du thiophene. L'effet de la porosite semble tout particulierement important, car il modifie profondement la selectivite des reactions. Il est cependant difficile d'etendre ces conclusions a d'autres reactions similaires, chaque cas necessitant une etude systematique de l'influence des divers parametres
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Hlatywayo, Tapiwa. "Coal fly ash and acid mine drainage based heterogeneous Fe catalysts Friedel-Crafts alkylation reaction." University of Western Cape, 2020. https://hdl.handle.net/11394/7295.
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Philosophiae Doctor - PhDThe catalytic support materials used in the present study are zeolite HBEA and MCM-41. These high silica zeolites were synthesised from coal fly ash (CFA) waste via a novel approach that involved a fusion step, acid assisted silica extraction and removal of Al, Ca and Na from the silica by treatment with oxalic acid. The generated silica was converted to HBEA and MCM-41 via conventional hydrothermal treatment. The metal incorporation onto HBEA was done via two approaches namely; liquid phase ion exchange (LIE) and wet impregnation (WI) while the loading on MCM-41 was only done via WI since the material does not possess exchange sites. The metal solution precursors were AMD and Fe extracted from CFA (FeAsh) via acid leaching followed by pH regulation by concentrated NaOH. This is the first time these solutions were tested as possible metal precursors in catalyst synthesis.
2021-08-30
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Kirk, Andrew. "Mesoporous supports for the catalysis of Friedel-Crafts alkylation and cyclialkylation reactions with sulfur-containing aromatics." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq31041.pdf.
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Montagne, Fabienne. "Les sels de terres rares en catalyse hétérogène des réactions de Friedel-Crafts : applications en polycondensation." Dijon, 1997. http://www.theses.fr/1997DIJOS033.
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En chimie fine, le réactif universel des réactions d'alkylation et d'acylation de composés aromatiques selon Friedel-Crafts est le trichlorure d'aluminium mais l'emploi de cet acide de Lewis présente plusieurs inconvénients : la réaction est au mieux stoechiométrique, le réactif est d'un usage unique et les effluents sont nuisibles à l'environnement. Les sels de terres rares déposés sur un support minéral sont d'excellents catalyseurs des réactions de Friedel-Crafts ; leur activité catalytique est nettement plus élevée que celle des chlorures de terres rares et leurs analogues coordonnés non supportés. Les conditions opératoires sont douces, l'isolement des produits ne nécessite pas d'hydrolyse et les catalyseurs, facilement éliminés du milieu réactionnel par simple filtration, sont recyclables. Différentes techniques d'analyse ont été utilisées pour caractériser les catalyseurs supportés et étudier l'influence des divers traitements sur la nature de l'espèce déposée. Après avoir évalué leurs performances catalytiques dans deux réactions tests, la gamme de réactivité des catalyseurs supportés a été étudiée. Les catalyseurs supportés ont également été étudiés dans des réactions conduites sous irradiation micro-ondes. Les différents tests ont confirmé qu'un accroissement de la température, module par la puissance du rayonnement micro-ondes, s'accompagne d'une augmentation du rendement ; la sélectivité est semblable à celle obtenue pour les réactions effectuées en chauffage traditionnel. L'application des réactions d'alkylation de type Friedel-Crafts à des réactions de polycondensation a conduit à la synthèse de nouveaux polybenzyles solubles, dont les caractéristiques physico-chimiques ont été déterminées.
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Fishlock, Daniel. "The Catalytic Intramolecular Friedel-Crafts Acylation of Meldrum's Acid Derivatives and The Total Synthesis of Taiwaniaquinol B." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/1226.
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The intramolecular Friedel-Crafts acylation of aromatics with Meldrum?s acid derivatives catalyzed by metal trifluoromethanesulfonates and other Lewis acids is reported. Meldrum?s acids are easily prepared, functionalized, handled, and purified. The synthesis of polysubstituted 1-indanones from benzyl Meldrum's acids was investigated thoroughly, and it was shown that a variety of catalysts were effective, whilst accommodating a diversity of functional groups under mild conditions. The scope, limitations, and functional group tolerance (terminal alkene and alkyne, ketal, dialkyl ether, dialkyl thioether, aryl methyl ether, aryl TIPS and TBDPS ethers, nitrile- and nitro-substituted aryls, alkyl and aryl halides) for a variety of 5-benzyl (enolizable Meldrum?s acids) and 5-benzyl-5-substituted Meldrum?s acids (quaternarized Meldrum?s acids), forming 1-indanones and 2-substituted-1-indanones respectively, are delineated. This method was further applied to the synthesis of 1-tetralones, 1-benzosuberones, and the potent acetylcholinesterase inhibitor donepezil.
Mechanistic investigations were undertaken to determine the rate-determining step in the acylation sequence using Meldrum?s acid, as well as to examine the role of the Lewis acid catalyst. Enolizable Meldrum?s acid derivatives can react via an acyl ketene intermediate under thermal conditions, while quaternarized Meldrum?s acid derivatives are thermally stable and only act as effective Friedel-Crafts acylating agents in the presence of a Lewis acid catalyst.
The total synthesis of (±)-Taiwaniaquinol B was completed. This natural product was the first ever isolated containing an unusual 6-5-6 fused ring system, and it also contains a hexasubstituted aromatic ring, and two all-carbon quaternary centers. This synthesis was accomplished via an intramolecular Friedel-Crafts acylation/carbonyl a-tert-alkylation reaction that exploits the unique chemistry of Meldrum?s acid. This novel methodology can be used to access a variety of highly substituted fused ring systems of various sizes.
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Gratais, Alexandre. "Chimie des acrylamides chiraux : nouvelles méthodologies et application à la synthèse de nouvelles architectures moléculaires." Thesis, Rouen, INSA, 2014. http://www.theses.fr/2014ISAM0013/document.
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Les réactions permettant la création de liaisons carbone-carbone sont des outils essentiels dans le domaine de la synthèse organique. Elles permettent d'accéder à des structures de plus en plus complexes. Cependant le contrôle de ces réactions en utilisant des partenaires hautement fonctionnalisés reste un enjeu majeur.Le développement de nouvelles méthodologies de synthèse basées sur la réactivité des acrylamides chiraux dérivés d'acides aminés est étudié dans ces travaux. Une nouvelle version de la réaction d'alkylation de pyrroles de type Friedel-Crafts a été développée en utilisant le caractère électrophile d'acrylamides chiraux hautement fonctionnalisés. Le pyrrole peut être monoalkylé ou dialkylé de façon sélective conduisant à de nouvelles structures hétérocycliques portant des enchaînements peptidiques pouvant contenir jusqu'à quatre résidus d'acides aminés. Les acrylamides chiraux portant un motif allyltriméthylsilane conjugué ont été utilisés comme nouveaux réactifs permettant des réactions d'allylation hautement diastéréosélectives et chimiospécifiques vis-à-vis d'aldéhydes. L'extension de cette méthodologie aux aldéhydes α- aminés a été réalisée et permet un accès aisé à des structures analogues des acides γ-aminésReactions allowing carbon-carbon bond creation are essential tools in the field of organic synthesis. These reactions are used to access to more and more complex structures. However their control in the case of highly functionnalized partners is still a serious concern.Development of new methodologies based on the reactivity of aminoacid derivating chiral acrylamides is reported. A new version of pyrrole alkylation reaction was developed using the electrophilic behaviour of highly functionnalized chiral acrylamides. Pyrrole can be selectivly monoalkylated or dialkylated leading to new heterocyclic structures bearing peptidic sequences containing up to four aminoacids residues. Chiral acrylamides bearing a conjuguated allyltrimethylsilane moiety have been used as new reagent in highly diastereoselective and chemospecific towards aldehydes allylation reactions. This methodology was extended to α-aminoaldehydes allowing easy access to γ-aminoacidsanalogues
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Joerger, Jean-Michel. "1. Catalyse asymétrique dans les liquides ioniques : applications à la réduction par transfert d'hydrogène et à l'époxydation ; 2. Réactions de substitutions électrophyles aromatiques avec des chloroformiates." Rennes 1, 2005. http://www.theses.fr/2005REN1S008.
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La première partie de ce travail étudie deux types de catalyses asymétriques dans des liquides ioniques. Nous avons montré qu'un catalyseur[Ru(p-cymène)(prolinanilide)], employé pour la réduction par transfert d'hydrogène de l'acétophénone, donne des cinétiques accélérées lorsqu'il est immobilisé dans [bmim][Pf6], et peut être recyclé quatre fois sans perdre trop d'activité ni d'excès énantiomérique. Des réactions d'époxydation ont été catalysées par un catalyseur de Jacobsen greffé sur support liquide ionique. La seconde partie est consacrée aux réactions de substitutions électrophiles aromatiques avec des chloroformiates d'alkyles ou d'aryles, catalysées préférentiellement par des oxydes métalliques. Après étude d'un grand nombre de paramètres, les chloroformiates d'alkyles nous ont permis de réaliser des alkylations électrophiles aromatiques avec des rendements pouvant dépasser ceux obtenus avec les halogénures. L'emploi des chloroformiates d'aryles est lui très limite
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Courant, Thibaut. "Multi-fonctionnalisation d’imines : synthèse de composés aminés α-β-fonctionnalisés par procédé photocatalysé et réactions asymétriques organocatalysées." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112308.
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Ce projet scientifique concerne le développement de nouvelles méthodes efficaces de fonctionnalisation d’imines par des procédés organocatalysés et photocatalysésDans un premier temps la réaction photocatalysée d’alkylation d’énamines en conditions douces à été étudiée. L’utilisation de photocatalyseurs sous forme de complexes organométalliques d’Iridium a permis de réaliser la double fonctionnalisation d’ènecarbamates, permettant ainsi d’obtenir des substituts d’imines hautement substitués. Ce procédé permet de s’affranchir de l’utilisation de métaux lourds et ne nécessite qu’une activation par la lumière visible pour fonctionner. Cette transformation radicalaire éco-compatible à par la suite été soumise à une étude mécanistique approfondie. Dans une deuxième partie, la réaction d’aza-Friedel-Crafts organocatalysée par des acides de Brønsted chiraux à été étudiée. Dans cette réaction, la bi-fonctionnalité des acides chiraux dérivés du BINOL a été exploitée. Elle permet l’addition énantiosélective d’une grande variété d’indoles substitués sur des acyl-pyrrolidinones générées in situ. Les composés synthétisés présentent des structures bioactives intéressantes notamment sur le système nerveux central.Enfin, la première réaction de Povarov asymétrique impliquant des amino-hétérocycles comme précurseurs de 2-azadiènes à été décrite. Cette étude s’appuie sur des travaux antérieurs du laboratoire et permet la synthèse des analogues hétérocycliques de tétrahydroquinoléines précédemment décrites. Le procédé met en jeu une séquence multicomposants réduction/Povarov catalysée par des acides phosphoriques chiraux et permet l’accès rapide à une large bibliothèque d’analoguesThe aim of this study is the development of new methodologies for imines functionalization by organocatalysed and photocatalysed processes.First, a photocatalysed alkylation reaction of enecarbamates have been described. The use of organometallic Iridium complexes allowed the double functionalization of enecarbamates leading to highly substituted imines surrogates. This process is a green alternative to the use of heavy metals and only needs visible light as an renewable energy source to proceed. This environment-friendly radical transformation has been submitted to mechanistic study.In a second part, an aza-Friedel-Crafts reaction organocatalysed by chiral Brønsted acid has been studied. The bi-fonctionnality of chiral phosphoric acids has been advantageously used to perform the Friedel-Crafts addition of various substituted indole to in situ generated acyl-iminium ions. The compounds obtained by this methodology are showing interesting biological activities on central nervous system. Finally, the first enantioselective Povarov reaction involving amino-heterocycles as 2-azadienes precursors has been reported. This reaction is based on previous lab reports and the synthesis of tetrahydroquinoline analogues has been described. The multicomponent reduction/Povarov reaction sequence catalyzed by chiral phosphoric acids derived gives a rapid access to a wide library of bioactives analogues
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Breistein, Palle. "Development of highly enantioselective organocatalyzed transformations." Doctoral thesis, Mittuniversitetet, Institutionen för naturvetenskap, teknik och matematik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-15621.
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Thaxton, Amber. "Synthesis of Novel Azetidines." ScholarWorks@UNO, 2013. http://scholarworks.uno.edu/td/1764.
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Azetidine is a four-membered nitrogen-containing heterocyclic ring that has recently received a great deal of attention as a molecular scaffold for the design and preparation of biologically active compounds. Structure-activity studies employing functionalized azetidines have led to the development of variety of drug molecules and clinical candidates encompassing a broad spectrum of biological activities.
Herein, the synthesis a novel series of 3-aryl-3-arylmethoxyazetidines is described. Selected 3-aryl-3-arylmethoxyazetidines were evaluated for their binding affinity to multiple monoaminergic transporters for the potential treatment of methamphetamine addiction. It was discovered that this scaffold exhibits high binding affinity (nM) for both the serotonin and dopamine transporters. In addition, a new method was developed for the synthesis of 3,3-diarylazetidines. This new approach provides a facile and efficient method to synthesize a variety of diaryl heterocycles including 3,3-diarylazetidines, 3,3-diarylpyrrolidines, and 4,4-diarylpiperidines in moderate to good yields.
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Goma, Jean Richard. "Applications de l'alkylation catalysée par transfert de phase dans la synthèse de coumarines, de chromones, d'amides et de photoxyéthers d'intérêt thérapeutique." Paris 11, 1989. http://www.theses.fr/1989PA114820.
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Fogain-Ninkam, Alain. "Synthèse de structures hétérocycliques incluant un motif isoindole par cyclisation intramoléculaire." Le Havre, 2000. http://www.theses.fr/2000LEHA0007.
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Ce mémoire présente la synthèse de structures polyhétérocycliques incluant un motif isoindole et isostères d'alcaloïdes naturels ou artificiels biologiquement actifs (anti-inflammatoires, anti dépresseurs, anti HIV,. . . ). La synthèse de thiazépinoisoindolones est décrite dans la première partie. L'étape de cyclisation est réalisée par acylation de Friedel et Crafts d'acides isoindolyl acétiques convenablement fonctionnalisés. Une tentative d'agrandissement du cycle thiazine par la réaction de Schmidt et la transposition de Beckmann a été entreprise sans succès. L'élaboration de structures hétérocycliques de type 1,2oxaza ou 1,2diaza à partir de n-hydroxy et de n-aminophthalimide constitue la deuxième partie de ce mémoire. La cyclisation est réalisée au moyen d'une a-amidoalkylation. Cette cyclisation a été précédée d'un réarrangement de l'ion n-acyliminium dans le cas de certains hydroxylactames précurseurs de polycycles pyridaziniques. Nous avons également réalise la synthèse d'une isoindolobenzoxadiazocine en mettant en jeu dans l'étape de cyclisation une réaction d'Aza-Wittig d'un précurseur azidé. Par ailleurs la réaction de Friedel et Crafts sur un acide 2-aralkyloxyisoindolyl-3-acetique a fourni une isoxazolinone et non l'isoindolo1,2benzoxazocine attendue ; résultat qui s'explique par la rupture de la liaison c b e n z y l i q u e - o sous l'influence de l'acide de Lewis. Nous avons enfin aborde la synthèse de pyrrolothia (ou oxa) diazépinoisoindolones ainsi que des pyrrolo1,3,4oxadiazinoisoindolones. L'étape de cyclisation de cette dernière série de composés s'est avérée délicate car les diols precurseurs polymerisent facilement en milieu acide. La seule condition relativement satisfaisante a consisté à opérer cette cyclodéshydratation en présence de silicagel.
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Chin, Ami Jun-Yee. "Part A Development of a Fluorescence Resonance Energy Transfer assay or high throughput screening for catalysts in the desymmetrization of meso substrates Part B Application of hydrazide based catalyst in Friedel-Crafts alkylation." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27118.
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Highthroughput methods have been increasingly applied to catalyst screening, however, efforts to use these for enantioselective measures are still lacking. We propose to apply Fluorescence Resonance Energy Transfer (FRET) as a highthroughput screening method to fulfill such a purpose. This concept is applied to the desymmetrization of meso substrates. The meso compound will be equipped with a recognition element for catalyst binding, two different fluorescence donor molecules to distinguish between the chiral centres and also a fluorescence acceptor molecule to suppress fluorescence. Upon catalytic hydrolysis, the fluorescence acceptor molecules will be discharged into solution and thus can be detected by use of a spectrophotometer. As each donor molecule has a characteristic fluorescence emission wavelength, measuring the respective fluorescence intensities will ultimately allow for one to rapidly determine the enantiomeric excess. Efforts towards establishing this FRET based assay are discussed herein.*
*Please refer to dissertation for diagrams.
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Beck, Daniel Antony Speedie, and beckautomatic@gmail com. "Stereoselective intramolecular Michael addition reactions of pyrrole and their application to natural product syntheses." The Australian National University. Research School of Chemistry, 2006. http://thesis.anu.edu.au./public/adt-ANU20070130.130009.
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Chapter one; (-)-Rhazinilam and (-)-Rhazinal: Alkaloids with Anti-mitotic Properties Derived from Kopsia teoi, provides the background information behind the motives that initiated this research project. The plant alkaloid (-)-rhazinilam [(-)-1] and its naturally-occurring derivative (-)-rhazinal [(-)-13] both exhibit potent anti-mitotic activities and, as such, are interesting targets for total synthesis. Chapter one is a review of the literature regarding these two compounds and discusses the occurrence, proposed biosynthetic origins, structural elucidation and biological activites of compound (-)-1 and that of its analogues including alkaloid (-)-13. Previous total syntheses of these two compounds are then examined, concluding with the only reported total synthesis of compound (-)-13. Developed within the Banwell research group, this total synthesis produced the racemic modification of alkaloid (-)-13 due to a lack of any stereocontrol in the key intramolecular Michael addition step. This unprecedented key step, involving cyclisation of the C2 of pyrrole onto an N-tethered and ?,?-disubstituted acrylate to produce a quaternary-carbon stereogenic centre, would be of greatly enhanced utility if it could be achieved in a catalytic-enantioselective fashion. The realisation of this goal is the central aim of the research conducted within this thesis.
¶
Chapter two; Investigating Asymmetric Induction in the Intramolecular Michael Addition of pyrrole to N-Tethered Acrylates and Related Species, introduces the model study used to direct research towards achieving the goal of asymmetric induction in the title process. The model is a somewhat simplified version of the original process used in the total synthesis of compound (-)-13 involving cyclisation of the C2 of pyrrole onto an N-tethered and ?-monosubstituted Michael acceptor, to produce a tertiary-carbon stereogenic centre. This simplification allows the rapid synthesis of a broad range of potential substrates for use in the title process, thus enabling the investigation of various different approaches to inducing asymmetry therein. High levels of asymmetric induction are observed with the use of chiral substrates or catalysts, facilitating the synthesis of both 6- and 7-membered rings annulated to pyrrole with construction of the relevant tertiary-carbon stereogenic centre in enantio-enriched form. For the reactions producing a 6-membered ring annulated to pyrrole, unambiguous proof of the absolute sense of asymmetric induction observed in the intramolecular Michael addition event is established using a chemical correlation study involving elaboration of a key indolizine-type cyclisation product, to the plant alkaloid of known absolute stereochemistry, (-)-tashiromine [(-)-75]. For the reaction producing a 7-membered ring annulated to pyrrole, the same information is obtained via X-ray crystallographic analyses of a dibrominated derivative of a key pyrroloazepine-type cyclisation product.
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Chapter three An Enantioselective Total Synthesis of the Alkaloid (-)-Rhazinal: An Anti-mitotic Agent Isolated from Kopsia teoi., focuses on the application of methodology developed in the previous chapter, to the original goal of inducing asymmetry in the intramolecular Michael addition reaction, involving cyclisation of the C2 of pyrrole onto an N-tethered and ?,?-disubstituted acrylate to produce a quaternary-carbon stereogenic centre. This is ultimately achieved in a catalytic-enantioselective fashion, resulting in the first such total synthesis of the anti-mitotic alkaloid (-)-rhazinal [(-)-13].
¶
Chapter four Extending the Reaction Manifold to the Syntheses of Related Natural Products: A Formal Total Synthesis of (+)-Aspidospermidine and Syntheses of (-)-Rhazinilam and (-)-Leuconolam from (-)-Rhazinal, describes three extensions to the reaction manifold used in the enantioselective total synthesis of alkaloid (-)-13:
The acquisition in an enantioselective manner, of an intermediate previously obtained in racemic form, en route to the racemic modification of the natural product (±)-aspidospermidine [(±)-134], constitutes a formal and enantioselective total synthesis of (+)-aspidospermidine
[(+)-134].
The direct deformylation of (-)-rhazinal [(-)-13], is carried out, to produce the parent alkaloid
(-)-rhazinilam [(-)-1].
The pyrrole ring present in (-)-rhazinilam [(-)-1] is oxidised, to produce the related natural product (-)-Leuconolam [(-)-12] which has not, hitherto, been prepared by total synthesis.
¶Chapter five contains the experimental procedures and characterisation data associated with compounds described in chapters two to four.
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Eck, Geneviève. "Synthèse partielle de la frédéricamycine A." Paris 6, 1986. http://www.theses.fr/1986PA066466.
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Le but du travail a été la synthèse d'un composé spirannique dicétonique modèle : le spiro (indane)-1,2'-(dimethoxy-4',7'indanedione-1',3')1. La première voie envisagée s'inspire de la synthèse de dialkyl-2,2 indanediones-1,3 par double réaction de Friedel-Crafts entre le dimethoxy-1,4 benzène et un chlorure d'acide dialkyl malonique. Ainsi, dans un premier temps le dimethoxy-1,4 benzène et l'acide cyclopentane dicarboxylique-1,1, en présence du réactif acide méthanesulfonique-anhydrique, fournissent le composé spirannique dicetonique résultat d'une double condensation avec un rendement de 45% : le spiro (dimethoxy)4,7 indanedione-1,3)-2, l'-(cyclopentane). La même réaction entre le dimethoxy-1,4 benzène et l'acide indane dicarboxylique-1,1 donne le composé 1 modèle avec un rendement de 8%. La deuxième voie étudiée a été la synthèse avec un rendement de 27% spiro (indane)-1,2'-(dimethoxy-4'7') 2 par alkylation du carbethoxy-1 indane par le chloromethyl-1 dimethoxy-2,5 benzène, saponification puis cyclisation par acylation intramoléculaire du produit obtenu. La transformation du compose monocétonique 2 en composé dicétonique 1 se fait par oxydation de la position benzylique avec un rendement de 8%. La derniere methode de construction de la structure spirannique de la frédéricamycine A a été la synthèse du spiro (indane)-1,1'-(cyclopentene-3'one-2') 3 par acylation desilylation du compose resultant de la saponification du produit d'alkylation du carbechoxy-1 indane par le (chloro-3 propenyl-1) trimethylsilane. Le produit 3 constituerait un accepteur de Michael pour une réaction de Hauser avec une phenylsulfonyl-3 isobenzofuranone-1 (3h) et fournirait ainsi un compose naphtoquinonique semblable à la frédéricamycine A.
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Paras, Nick Anthony Dervan Peter B. "Enantioselective organocatalytic Friedel-Crafts alkylations of heterocycles and electron-rich benzenes /." Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-06012004-190154.
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Iraqi, Ahmed. "Activation des hydrocarbures alkylations sélectives de Friedel et Crafts en catalyse acide par transfert d'hydrure /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37606057s.
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Vukovic, Vuk. "Synergistic effect of acids and HFIP on Friedel-Crafts reactions of alcohols and cyclopropanes." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF068.
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L'activation catalytique d'alcools vers la formation déshydrative de liaisons chimiques sans pré-activation est devenue un intérêt de recherche majeur au cours des deux dernières décennies. Dans cette thèse, l’effet synergique particulier des acides forts en tant que catalyseurs dans l’hexafluoroisopropanol (HFIP) comme solvant de diverses classes de carbocations instables dans la chimie de Friedel-Crafts a été étudié. Il a été constaté que pour la première fois, les réactions de Friedel-Crafts d'alcools benzyliques primaires fortement désactivés, catalysées par un acide, se déroulaient facilement, en raison des phénomènes d'agrégation induits par l'acide dans HFIP. Une stratégie similaire a été utilisée pour l'activation d'alcools propargyliques, comme nouvelle voie d'accès sélectif aux allènes et indènes portant la fonction CF3, à partir des mêmes composés de départ. De plus, ce système catalytique a été appliqué avec succès pour les réactions de Friedel-Crafts de cyclopropanes de type non activés et donneur-accepteur. Enfin, il a été découvert que le HFIP pouvait atténuer le réarrangement de carbocation classique dans les alkylations de Friedel-Crafts, permettant l’accès aux produits avec chaînes alkyle linéaires en une seule étape à partir d’alcools aliphatiques linéairesThe catalytic activation of alcohols towards dehydrative bond formation in the absence of pre-activation has become a major research interest over the past two decades. In this thesis, the peculiar synergistic effect of strong acids as catalysts in hexafluoroisopropanol (HFIP) as solvent on various classes of unstable carbocations in Friedel-Crafts chemistry was investigated. It was found that for the first time, Brønsted acid catalyzed Friedel-Crafts reactions of highly electronically deactivated primary benzylic alcohols proceeded smoothly due to the acid-induced aggregation phenomena in HFIP. A similar strategy was used for the activation of propargylic alcohols as a new route to selectively access CF3-substituted allenes and indenes from the same starting compounds. Furthermore, this catalytic system was succesfully applied for Friedel-Crafts reactions of unactivated and donor-acceptor cyclopropanes. Finally, it was discovered that HFIP can mitigate against classical carbocation rearrangement in Friedel-Crafts alkylations, allowing access to linear alkyl chain products in a single step from linear alkyl alcohols
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Bush, Alexander Graham. "Part A: Design of new camphor-based hydrazide organocatalysts and their applications to enantioselective Friedel-Crafts alkylations Part B: The development of the palladium catalyzed addition of organoborates to alkynyl esters: Synthesis of trisubstituted olefins as single isomers." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28272.
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Part A. Asymmetric synthesis is a growing field in synthetic and medicinal chemistry. Investigations into the use of organocatalysts to engender chirality into organic molecules is of particular interest. Herein we present the study of the efficiency of camphor-based hydrazide organocatalysts in the asymmetric Friedel-Crafts alkylations of N-methylindole with alpha,beta-unsaturated aldehydes. In addition, the applicability of newly designed second-generation camphor-based hydrazide catalysts will be examined.*
Part B. The synthesis of trisubstituted olefins represents an intriguing target in organic chemistry. However, the stereocontrolled synthesis of trisubstituted olefins can prove to be difficult, as mixtures of isomers are often obtained. A new methodology is presented herein that allows for the synthesis of single isomer trisubstituted olefins by a palladium catalyzed reaction of alkynyl esters with aryl and vinyl boronic acids under mild reaction conditions by using the simple phosphine ligand Et3P. The process provides alpha,beta-unsaturated esters with complete control of the stereochemistry and regiochemistry at the newly formed the double bond.*
*Please refer to dissertation for diagrams.
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Hlatywayo, Tapiwa. "Supported metal catalysts for friedel-crafts alkylation." 2013. http://hdl.handle.net/11394/3565.
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Doctor EducationisThe research focused on the synthesis, characterisation and activity of zeolite supported metal catalysts for the Friedel-Crafts alkylation of benzene with t-butyl chloride. Alkyl benzenes are traditionally produced via systems that employ the use of Lewis acids or strong mineral acids. There have been widespread concerns over these approaches based on their environmental impacts and separation difficulties. Recent approaches have endeavoured the much to use more environmentally eco-friendly systems and zeolites have proved to be versatile support materials. The use of zeolites has also shown to greatly improve product selectivity as well as easing separation constraints. However the adoption of zeolites on large scale Friedel-Crafts alkylation has been hampered by the high cost of zeolite production from commercial sources. On the other hand fly ash has been found to be a viable starting material for zeolite synthesis. Apart from that South Africa is faced with fly disposal challenges and there is continual accumulation of fly ash at the coal fired power stations, which provide about 77 % of the power produced in the country. In this light the use of fly ash will help to reduce the disposal constraints as well as providing a cheap starting material for zeolite synthesis. In this study the hierarchical Zeolite X has been successfully synthesised from fly ash via a hydrothermal treatment. The zeolite was then loaded with Fe/Mn via two approaches namely liquid phase ion exchange and incipient wetness impregnation. For comparison purposes seasoned commercial support materials namely HBEA and MCM- 41 were also loaded with the same metals and characterised with various techniques namely; HRSEM, EDS, HRTEM, XRD, SAED, ICP-OES and N2 adsorption analysis, It was found from the characterisation undertaken that the integrity of the respective supports was generally retained upon metal loading. Both the ICP-OES and the EDS proved that the desired metals were successfully introduced onto the zeolitic support materials. The calculated percentage metal loading for the catalysts prepared via incipient wetness impregnation was closely related to the actual values obtained from the ICP-OES analysis for both the monometallic and the bimetallic catalysts (Fe/Mn). It was observed that the amount of metal that can be introduced on a zeolite via liquid phase ion exchange is largely dependent on the cation exchange capacity of the zeolite Supported metal catalysts for FC alkylation Page v and of the catalysts prepared using 0.25 M Fe solution it was found that Zeolite X had the highest Fe wt% loading of 11.4 %, with the lowest loading of 2.2 % obtained with the MCM-41 supported catalyst. The XRD patterns for the both HBEA and the MCM-41 supported metal catalysts resembled the patterns of the respective prestine support materials except in the case of catalysts with anFe wt % of more than 10, which exhibited peaks due to the Fe2O3 crystallites. In the case of the hierarchical Zeolite X, the metal loaded support had a significant reduction in the XRD peak intensities. The prepared catalysts were tested for the alkylation of benzene with t-butyl chloride. The benzene was also used as the solvent. The alkylation reaction was carried out in a round bottomed flask under reflux conditions and stirring at a temperature of 45 oC over a period of 5 h. A total of 18 catalysts was tested and the highest percentage conversion of 100 % was obtained with the 10%FeH after a reaction time of 2 h. The general trend obtained with the majority of the catalysts was characterised with a rapid initial increase and then steady state was achieved. Generally after a reaction time of 3 h almost all the catalysts had reached steady state in terms of the percentage conversion obtained. The outcomes reflect that the inclusion of Mn does not enhance the conversion but rather decreases it. It was also found that the Mn was not active in the alkylation of benzene as shown by the inactivity of the 10%MnM, where 10% by weight Mn was loaded on MCM-41. However the other monometallic catalysts containing Mn supported on Zeolite X and HBEA were found to be active. The activity is attributed to the presence of Brønsted acid sites in these zeolites which are not present in MCM-41. The selectivity studies reflect that the inclusion of Mn does slightly improve the selectivity towards the formation of the monoalkylated product (t-butyl benzene). The highest selectivity of 91.1 % was obtained with the 10%FeMnM after a reaction time of 4 h. MCM-41 supported catalysts had a relatively higher selectivity compared to the other supports. Considering the Fe monometallic catalysts tested it generally can be said that the yield were in the order HBEA > MCM-41 > Zeolite X. It however should be noted that the percentage yield is calculated from the conversion and selectivity percentages, this implies that the factors affecting these parameters will consequently affect the percentage yield obtained. Supported metal catalysts for FC alkylation Page vi The alkylation reaction was found to be characterised by the formation of two intermediate products which could not be identified. These products were formed during the transient start up stages of the reaction and would disappear from the reaction mixture with longer reaction times, and after 3 h in almost all the reactions studied the intermediates were not detected in the reaction mixture. The main products found were the monoalkylated product (desired product) and the para isomer (1,4-t-di-butyl benzene). There were no other dialkylated isomers or trialkylated products detected. The formation of the para isomer was usually after a reaction time of 2 h in most reactions. The research managed to show that the hierarchical Zeolites X can be synthesised from fly ash and ion exchange and incipient wetness impregnation are appropriate approaches that can be used to introduce Fe/Mn onto the support materials studied. The catalysts prepared were active to varying degrees in the Friedel-Crafts alkylation of benzene with t-butylchloride, with the exception of the 10%MnM which was found to be inactive.
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陳建宇. "Synthesis of the Indolyl-Nitroalcohols via the Friedel-Crafts Alkylation–Henry Reaction Process." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/djsup3.
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碩士國立中正大學
化學暨生物化學研究所
106
In this thesis, we have synthesized a series of indole derived nitro alcohols containing multiple chiral centers by using Friedel-Crafts alkylation of indoles with nitroolefins followed by Henry reaction with different aldehydes. In addition, the structure of nitro alcohols, e.g. compound 37b, was confirmed by X-ray crystallographic analysis of the single crystal.
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王星勳. "Organotungsten lewis acid catalyzed friedel-crafts alkylation and[2+2+2]cyclotrimerization reactions." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/89556292293678620121.
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Chiu, Hui-Tzu, and 邱惠慈. "Novel Silver N-heterocyclic Carbene Complex Promoted the Palladium-Catalyzed Friedel-Crafts Alkylation Reaction." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/63726533720295244853.
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碩士國立中興大學
化學系所
105
Indole and its derivatives are important central building blocks for various biologically active natural products, agrochemicals, and drugs. In particular, the 3-substitued indoles have advantages in medicinal chemistry due to its recurring presence among antiviral agents. The synthesis of 3-substitued indoles has attracted considerable attention from chemists. One of the most important methods to synthesize 3-substitued indole derivatives is accomplished by the Friedel–Crafts alkylation reaction of indoles to nitroalkenes. In this study, compound 21 was synthesized from o-phenylenediamine and triethyl orthoformate, followed by coupling with 4-iodoanisole in the presence of CuI to give compound 22. The bis-benzimidazolium salt 17b was obtained from 22 linked with dibromopentane, then reacted with silver oxide to form silver carbene complex 23 (NHC–Ag). Palladium carbene complex (NHC–Pd) was formed by metal–metal exchange of Pd(OAc)2 with 23 in situ to catalyze the Friedel–Crafts alkylation. The catalytic system comprised of Pd(OAc)2/NHC–Ag shows high efficiency for the Friedel–Crafts alkylation over an array of indoles and activated or non-activated nitroolefins in the presence of low Pd-catalyst loading (2 mol%) at 30 °C. Particularly noteworthy is that our results are the first successful application for NHC–Ag complex 23 directly catalyzed the C–C bond formation of nitroolefins with indoles. Accroding to preliminary study results, it is found that the 3-substitued indoles were obtained by the the Friedel–Crafts alkylation of indoles to nitroalkenes using NHC–Ag complex 23 (0.5 mol %) as a catalyst in moderate yield. Further studies for NHC–Ag complex catalyzed the Friedel–Crafts alkylation will be explored in due course. In conclusion, we have developed an efficient bis-benzimiadzolium salt and its silver complex which are air/moisture stable and accessible with simple synthetic steps. The Friedel–Crafts alkylation reaction of indoles with nitroalkenes was successfully carried out under mild conditions by using the catalytic system generated from NHC–Ag complex 23 and Pd(OAc)2 in situ, which improved the disadvantages of the high-loading of catalyst, the high reaction temperature and the long reaction time.
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Chang, Chia-Hao, and 張嘉豪. "Organocatalytic Asymmetric Friedel-Crafts Alkylation through Electron-rich Phenols with Alkylideneindolenines: The Synthesis of Chiral Indole Derivatives." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/efb5m9.
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博士中原大學
化學研究所
107
Abstract Our purpose is to develop the organocatalytic asymmetric Friedel-Crafts alkylation reaction of electron-rich phenols to alkylideneindolenines generated in situ from arenesulfonylalkylindoles. These reactions were catalyzed by (thio)urea- based cinchona alkaloid bifunctional organocatalysts, producing chiral indole derivatives in yields (up to 99%) and enantioselectivites (up to 97%).
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[Verfasser], Joni. "Development of a sustainable technology platform for the homogeneous Friedel-Crafts alkylation using acidic ionic liquid catalyst = Über die Entwicklung einer nachhaltigen Friedel-Crafts-Alkylierung mittels saurer ionischer Flüssigkeiten / vorgelegt von Joni." 2009. http://d-nb.info/997283629/34.
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Paras, Nick Anthony. "Enantioselective Organocatalytic Friedel-Crafts Alkylations of Heterocycles and Electron-Rich Benzenes." Thesis, 2004. https://thesis.library.caltech.edu/2353/1/NParas.pdf.
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The development of the first organocatalytic asymmetric Friedel-Crafts alkylation is described in the context of conjugate additions of pyrroles to a,b-unsaturated aldehydes. Catalytic amounts of chiral imidazolidinone salts are used to activate the electrophile component via reversible formation of iminium ions. Ensuing conjugate additions of pyrroles afford aldehyde products in good yield and high enantiopurity using a range of alkyl-, aryl-, and heteroatom-substituted enals and nucleophiles. This reaction demonstrates the feasibility of using iminium catalysis to promote reactions of electron-deficient olefins beyond simple cycloaddition reactions. Observations were also made regarding the role of Bronsted acid cocatalysts in these organocatalytic reactions. The synthetic utility of asymmetric conjugate additions of pyrroles was demonstrated in a concise, enantioselective synthesis of the analgesic Ketorolac.
An enantioselective organocatalytic conjugate addition of electron-rich benzenes to a,b-unsaturated aldehydes has been developed. A new chiral secondary amine promotes exclusive para-alkylation of dialkylamino-substituted benzenes in good yield and with a high degree of stereocontrol. The process tolerates a range of substitutents on the electrophile component as well as a high degree of flexibility in the ortho- and meta-positions on the benzene ring. Particularly, the unique ability of this methodology to efficiently generate bisbenzyllic stereocenters by addition of electron-rich benzenes to cinnamaldehyde derivatives is demonstrated.
A general procedure for the cleavage of dialkylamino substituents from aromatic rings has also been developed. To accomplish this cleavage, a dialkylaniline is first converted to the corresponding quaternary ammonium salt with methyl iodide or methyl trifluromethanesulfonate. In a second step, dissolving metal reduction of the salt liberates the deaminated arene in high yields for the overall process. A range of alkyl, aryl, and heteroatom substitutions at the ortho, meta, and para positions were tolerated without significant decrease in reaction efficiency or yield. Deamination of aniline substrates bearing stereogenic centers para to the dialkylamino functionality proceeded with complete retention of enantiopurity. The combined utility of the asymmetric aniline alkylation and the new deamination methodology was demonstrated in the first enantioselective synthesis of the anticholinergic drug (R)-Tolterodine.