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Synthèse régio- et stéréosélective du 4,4,4-trifluorobut-2-énoate d'éthyle porteur d'un groupement tributylstannyl en position alpha ou bêta : réactivité cupro-catalysée des vinylétains en l'absence de complexes du palladium / Regio- and stereoselective synthesis of 4,4,4-trifluorobut-2-enoate carrying a tributylstannyl group in position alpha or beta : copper-catalyzed reactivity of vinyltins in the absence of palladium complexesZine, Khalid 16 December 2011 (has links)
Vu l’importance des molécules fluorées dans différents domaines et vu la réactivité engendrée par le 4,4,4-trifluorobut-2-ynoate d’éthyle 1 lors des travaux antérieurs réalisés au laboratoire, nous avons décidé d’étudier le comportement de dérivé fluoré 1 vis-à-vis d’hydrure tributylétain sans l’emploi de catalyseurs ou d’additifs. Le but est d’accéder à de nouveaux synthons fluorés par voies originales.Après une étude préliminaire pour effectuer cette réaction d’hydrostannation dans les meilleures conditions, nous avons réalisé pour la première fois la synthèse totalement régio- et stéréosélective des vinylétains (Z)-2α et (Z)-2β par un simple choix de solvant et sans l’utilisation d’aucun additif. Ces résultats inédits et très encourageants, nous ont conduis à étendre cette stratégie à d’autres hydrures comme l’hydrure de diphénylphosphine et l’hydrure de triphénylgermane..Les vinylétains (Z)-2α et (Z)-2β- de configurations bien définies sont des réactifs de choix pour élaborer de nouvelles structures fonctionnelles trifluorométhylées. En effet, le couplage cupro-catalysé de ces vinylétains en présence d’une quantité catalytique de CuI (10 moles%) avec une variété de bromures d’allyles, de propargyles, d’aryles, de benzyles et d’alcynyles conduisent à une grande variété de composés fluorés jamais décrits dans la littérature.Les méthodes de synthèse développées dans ce travail sont originales et permettent la synthèse d’une grande famille de composés fluorés avec un moindre coût. / The development of a simple method to obtain perfluoroalkylated building blocks for their subsequent utilization in the synthesis of Rf-containing compounds is therefore essential to organofluorine chemistry. Perfluoroalkylated vinyl metals constitute an important class of these building blocks.In order to prepare a new perfluoroalkylated bulding blocks, we investigated transition metal-catalyzed-free hydrostannylation of ethyl 4,4,4-trifluorobut-2-ynoate 1. The hydrostannylation took place smoothly in the absence of additive, providing regioselectively high yields of the corresponding α or β stannylated alkenoates depending on the nature of the solvent used. Indeed, we have demonstrated that the hydrostannylation of 1 in hexane provided the β-stannylated product with high regioselectivity (>95%) and excellent yield (>97%). Using methanol as solvent, total α-regioselectivity of the hydrostannylation of 1 was observed, providing α -tributylstannylacrylate as the sole regioisomer in a nearly quantitative yield.Theses new vinyltins reagents readily undergo copper (I) catalyst coupling reactions with various electrophiles as allyl, propargyl, benzyl and alkynyl bromides to provide good yields of the new corresponding acrylates esters bearing a β-trifluoromethyl group.This method provided a new efficient entry to this important class of compounds
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Untersuchungen zur Synthese fluoreszenzaktiver aromatischer Polyzyklen durch Palladium-katalysierte Domino-C‒H-Aktivierungen / Investigation of the Synthesis of fluorescent aromatic Polycycles via Palladium-catalyzed domino C‒H-activationsEichhorst, Christoph 09 October 2014 (has links)
Fluoreszenzfarbstoffe wurden über neuartige Palladium-katalysierte Domino-Reaktionen synthetisiert, die aus einer Sonogshira-Reaktion, zwei Carbopalladierungen und einer C-H-Aktivierung bestanden.
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Synthèses de molécules polycycliques par arylation C(sp³)-H intramoléculaire catalysée par le palladiumPierre, Cathleen 16 October 2012 (has links) (PDF)
La synthèse de produits complexes se doit de prendre en compte de nouvelles méthodes desynthèse plus efficaces, dont la fonctionnalisation de liaisons carbone-hydrogène. Dans cecontexte, la catalyse homogène par les métaux de transition s'est avérée performante, tout encontrôlant la régio- et la chimiosélectivité de la réaction. Les travaux de thèse présentés dansce manuscrit témoignent de l'efficacité de cette stratégie pour la construction rapide decomplexité moléculaire.Dans un premier temps, nous nous sommes intéressés à l'utilisation de précurseurs chlorés, cequi a permis d'étendre significativement le champ d'application de l'arylation C(sp3)-Hintramoléculaire pallado-catalysée. Ces travaux ont conduit à la synthèse de nombreuxhétérocycles, difficilement accessibles par d'autres voies de synthèse plus traditionnelles.Dans un deuxième temps, le développement d'une méthodologie de double arylation C-Hnous a permis de synthétiser des molécules polycycliques aux squelettes originaux. Une seuleet même espèce catalytique permet dans ce cas de réaliser les deux opérations d'activation CHavec succès.Par la suite, nous avons montré qu'il était possible de synthétiser des composés énantioenrichispar arylation C(sp3)-H intramoléculaire asymétrique. Pour cela, les ligands chiraux detype phosphépine se sont avérés particulièrement performants, et induisent desénantiosélectivités prometteuses.Enfin, notre attention s'est portée vers la synthèse de polycycles par arylation C(sp3)-Hintramoléculaire deshydrogénante. Les résultats encourageants obtenus apparaissent commeune preuve de concept dans ce domaine, où très peu de travaux de recherche ont été rapportés.
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Étude de nouvelles méthodologies d'arylation directe en séries azole et pyridine : Application à la synthèse de coeurs de thiopeptides antibiotiques de la série dLassalas, Pierrik 11 December 2012 (has links) (PDF)
Face à l'apparition grandissante de souches bactériennes multi-résistantes à l'arsenal d'antibiotiques actuels, les thiopeptides antibiotiques, bien que connus depuis plus de 60 ans, suscitent actuellement un fort regain d'intérêt. En effet, cette classe de molécules présente une forte activité antibiotique contre des souches bactériennes résistantes et multirésistantes, et met en œuvre deux modes d'inhibition originaux de la synthèse protéique encore inexploités en thérapie antibiotique humaine. Leur développement pharmacologique est en particulier freiné par la difficulté de préparation de ces molécules très complexes. L'élaboration d'une stratégie innovante de synthèse de la partie la plus complexe de ces molécules, le cœur hétérocyclique est étudiée dans ce travail. Cette approche repose sur l'étude et la valorisation de nouvelles méthodologies de fonctionnalisation directe des liaisons C-H et C-X de mono- et bis-thiazoles avec une large gamme d'hétéroaromatiques. Sa viabilité est démontrée par la préparation du cœur hétérocyclique commun aux amythiamicines.
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New Methodologies in Organic Chemistry: Applications to the Synthesis of α-Amino Acids and Natural ProductsHirner, Sebastian January 2009 (has links)
This thesis deals with the development and application of new synthetic methodology in organic chemistry. The first part describes the development of a new protocol for the synthesis of 3-pyrrolines by means of a microwave-assisted ring-expansion reaction of 2-vinylaziridines. In addition, this methodology is implemented as a key-step in a formal total synthesis of the antibiotic (-)-anisomycin. In the second part, a new methodology for the synthesis of arylglycines from Weinreb amides is described. In this procedure, a Grignard reagent is added to the iminium ion formed from the Weinreb amide upon treatment with a base. When a chiral amide is used, the nucleophilic addition proceeds with high diastereoselectivity. Finally, an easy and straightforward synthesis of α-amino amides via a base-mediated rearrangement of modified Weinreb amides into N,O-acetals is presented. Subsequent arylation, alkylation, alkenylation or alkynylation of this intermediate affords the corresponding α-amino amides in excellent yields. Furthermore, a more generalized protocol for the α-arylation of Weinreb amides lacking an α-amino moiety is also discussed. / QC 20100719
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Palladium-Catalyzed intramolecular sp3 C–H functionalization : studies in cyclopropyl and heterocyclic motifsLadd, Carolyn L. 12 1900 (has links)
No description available.
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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 / Development of new C-H and C-X direct arylation methodologies in thiazole and pyridine series : application to the synthesis of the heterocyclic core of thiopeptides antibiotics in the d seriesLassalas, Pierrik 11 December 2012 (has links)
Face à l’apparition grandissante de souches bactériennes multi-résistantes à l’arsenal d’antibiotiques actuels, les thiopeptides antibiotiques, bien que connus depuis plus de 60 ans, suscitent actuellement un fort regain d’intérêt. En effet, cette classe de molécules présente une forte activité antibiotique contre des souches bactériennes résistantes et multirésistantes, et met en œuvre deux modes d’inhibition originaux de la synthèse protéique encore inexploités en thérapie antibiotique humaine. Leur développement pharmacologique est en particulier freiné par la difficulté de préparation de ces molécules très complexes. L'élaboration d'une stratégie innovante de synthèse de la partie la plus complexe de ces molécules, le cœur hétérocyclique est étudiée dans ce travail. Cette approche repose sur l'étude et la valorisation de nouvelles méthodologies de fonctionnalisation directe des liaisons C-H et C-X de mono- et bis-thiazoles avec une large gamme d’hétéroaromatiques. Sa viabilité est démontrée par la préparation du cœur hétérocyclique commun aux amythiamicines. / Due to the emergence of multiresistant bacterial strains to standard antibacterial treatments, thiopeptides antibiotics are actually highly considered, though they are known for 60 years. They show an excellent antibiotic activity against multiresistant bacterial strains, and implement two originals inhibition mechanisms of protein synthesis, still unemployed in human therapy. However, the difficulty to prepare these complex macromolecules limits their pharmacological development. The development of a new strategy to synthetize the most complicated part of these macromolecules, their heterocyclic core, is studied here in. This approach is based on the study and the exploitation of novel direct C-H and C-X transition-metal-catalyzed couplings of mono- and bithiazoles units with a broad panel of heteroaromatics. Its viability is here demonstrated trough the multi-step synthesis of the common heterocyclic core of amythiamicins.
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Exploiting Substituent Effects to Control the Mechanochromic Response of Spiropyran-containing CopolymersKempe, Fabian 18 May 2021 (has links)
Mechanochromic polymers respond to external force by changing their color. This can be achieved by the incorporation of a molecular switch such as spiropyran (SP) into polymers. SPs can be isomerized by mechanical force from their colorless form into colored merocyanines. Main chain copolymerization of spiropyrans allows investigation of their mechanochromic behavior and potential use as force sensors.
So far, several covalent polymer matrices have been used to investigate the mechanochromic response of SPs, among them poly(ε caprolactone) (PCL). Less investigated is how the mechanochromic response can be fine-tuned by substituent effects. First, PCL with differently substituted spiropyrans at the chain’s midpoint were used in order to investigate the effect of different substituents and their regiochemistry on the isomerization behavior of SPs under mechanical stress. A low activation barrier was observed for NO2 substitution of “ortho”-spiropyrans compared to no substitution (R = H).
In order to investigate phenyl-substituted “para,para” spiropyrans, a newly developed kinked polyarylene was employed as covalent matrix material. This new polyarylene (PmmpP) has a meta,meta,para connection in its backbone and exhibits excellent mechanical properties. Its high strength allows the isomerization of this molecular switch with a large activation barrier. The phenyl-substituted “para,para” spiropyran showed transient mechanochromism and was switched 25 times in force-and-release cycles. The synthesis of PmmpP was carried out by a Suzuki polycondensation in three steps from commercial starting materials.
To further capitalize on the simplicity and properties of PmmpP, a two step synthesis of a semifluorinated kinked polyarylene was demonstrated by direct arylation polycondensation with tetrafluorobenzene (F4). This partially fluorinated PmmpF4 was synthesized with a variety of side-chains. Resulting polymers exhibited a large range of glass transition temperatures, allowing for the production of tailor-made smart materials.
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[en] SYNTHESIS OF N-TOSYL AZA-CARBAPTEROCARPANES AND SPIRO ISO-INDOLINES WITH POTENTIAL ANTICANCER ACTION IN LEUKEMIA STRAINS / [pt] SÍNTESE DE N-TOSIL AZA-CARBAPTEROCARPANOS E ESPIRO ISO-INDOLINAS COM POTENCIAL AÇÃO ANTITUMORALJOSEANE ALVES MENDES 20 May 2021 (has links)
[pt] Neste trabalho foi desenvolvida a síntese de novos análogos do tipo N-tosil-aza-carbapterocarpanos com potencial ação antiproliferativa em linhagens de leucemia e mama.Os compostos aza-carbapterocarpanos e espiro-iso-indolinas, foram preparados através de abordagens sintéticas distintas e classificadas em Grupo I e II respectivamente. A etapa chave para obtenção dos compostos do grupo I foi a reação de aza-arilação do tipo Heck catalisada por paládio a partir de tetralonas comerciais e N-tosil-iodoanilinas substituídas previamente sintetizadas. Três moléculas deste grupo foram avaliadas quanto a sua ação antiproliferativa em linhagens de leucemia e mama. Dentre estas, o composto N-tosil-aza-carbaptercarpeno apresentou IC50 = 1,93 (mais ou menos) 0,88 micrômetros, 2,18 (mais ou menos) 1,47 micrômetros e 2.89 (mais ou menos) 0,92 micrômetros nas linhagens de leucemia K562, lucena-1 e FEPS, respectivamente, e na linhagem de mama MDA-MB-231 IC50=33.37 (mais ou menos) 3.98 micrômetros. Por outro lado, o composto aza-carbapterocarpeno foi inativo nestas mesmas linhagens, indicando que na ausência do grupo arilsulfonamida a ação antileucêmica não ocorre. Os compostos do grupo II, denominados espiro iso-indolinas, foram sintetizados através da adição diastereosseletiva de organomagnesío às N-terc-butano-sulfiniliminas quirais, seguida de uma aminação de Buchwald-Hartwig intramolecular catalisada por paládio. As N-terc-butano-sulfiniliminas foram obtidas através de tetralonas, cromanonas e tiocromanonas comerciais em uma reação de condensação com as N-tert-butanosulfinamidas comerciais em micro-ondas em uma abordagem livre de solvente utilizando tetraetóxido de titânio. Após as reações de adição nucleofílica com organomagnésio, remoção do auxiliar quiral e ciclização intramolecular, os compostos forma obtidos enantiomericamente puros e foram avaliados em linhagens de leucemia K562 e FESP. Embora estes compostos tenham apresentado baixa potência frente às linhagens testadas (IC50 entre 31,85 mais ou menos 3.0 micrômetros e 77,58 (mais ou menos) 5.76 micrômetros), pôde-se observar que há diferenças relevantes entre os enantiômeros, assim o como apresentam sensibilidade colateral, atuando em linhagens multiresitentes. / [en] In this work, the synthesis of new N-tosyl aza-carbapterocarpane analogues with potential antiproliferative action in leukemia and breast cell lines was developed. The aza-carbapterocarpanes and spiro-isoindolines compounds were prepared using different synthetic approaches and classified in Group I and II respectively. The key step for obtaining group I compounds was the palladium catalyzed Heck-type azaarylation reaction from commercially synthesized substituted tetralones and substituted N-tosyl iodoanilines. Three compounds of this group were evaluated for their antiproliferative action in leukemia cell lines and breast cancer cells lines. The compound N-tosyl-aza-carbaptercarpene presented IC50 = 1,93 0,88 , 2,18 (plus or minus) 1,47 micrometers e 2.89 (plus or minus) 0,92 micrometers. On the other hand, the aza-carbapterocarpene compound was inactive in these same lines, suggesting the role of the absence of the arylsulfonamide group for the antileukemic activity does not occur .The group II, denominated spiroisoindolines, were synthesized by diastereoselective addition of organomagnesium to chiral N-tert-butane sulfinylimines, followed by a palladium catalyzed intramolecular Buchwald-Hartwig amination. The N-tert-butane sulfinylimines were obtained through commercial tetralones, chromanones and thiochromanones by the condensation reaction with commercial N-tert-butanesulfinamides in a solvent free sistem using titanium tetraethoxide. After nucleophilic addition reactions with organomagnesium, chiral auxiliary removal and intramolecular cyclization, the compounds were obtained enantiomerically pure and were evaluated in K562 and FESP leukemia lines. Although these compounds presented low potency compared to the tested lines (IC50 between 31.85 (plus or minus) 3.0 micrometers and 77.58 (plus or minus) 5.76 micrometers), it was observed that there of them present relevant differences between enantiomers as soon as collateral sensitivity, acting in leukemia multiresistent cell lines.
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Synthesis and Characterization of Diketopyrrolopyrrole- based Copolymers for Organic Electronic ApplicationsWang, Qian 04 June 2024 (has links)
Diketopyrrolopyrrole (DPP)-based polymers currently rank among the best performing organic materials for high charge carrier mobility applications due to their high structural planarity and the simple synthetic access. Through chemical modifications on DPP-based polymers, the type of charge carrier transport (p-type, n-type or ambipolar) and the charge carrier mobility can be both modulated. In this thesis, the synthesis of a new n-type dithiazolyldiketopyrrolopyrrole (TzDPPTz)-based copolymer PTzDPPTzF4 with tetrafluorobenzene (F4) as comonomer is reported. PTzDPPTzF4 has a deeper lowest unoccupied molecular orbital (LUMO) energy level compared to the existing dithienyldiketopyrrolopyrrole (ThDPPTh)-based copolymer PThDPPThF4 due to the electron-deficient thiazole flanking units on the bicyclic DPP core. Moreover, the influence of homocoupling (hc) defects and backbone conformation on the properties of PTzDPPTzF4 is systematically investigated. Lastly, in order to further modulate the structural and electrical properties of DPP-based copolymers, polar side chains and comonomers with a different electron-withdrawing ability are introduced to the polymer backbone. In detail, a series of PTzDPPTzF4 polymers with similar molecular weight but varying TzDPPTz hc content from 0.6 – 12.4% is prepared via direct arylation polymerization (DAP) for the investigation of the hc-property relationship. Hc defects are found to red-shift the absorption, decrease the photoluminescence, and lower the LUMO energy level. In contrast, an influence on the film morphology or electron mobility is not observed. In order to study the conformation-property relationship, a structural variation in the DPP monomer is explored, i.e. the replacement of Tz by Th. To this end, a detailed comparative study of the properties between PTzDPPTzF4 and PThDPPThF4, which are prepared via DAP and have both comparable molecular weight and hc content, is presented. It is found that the replacement of Tz flanking units by Th flanking units on the DPP core has significant impact on the backbone conformation due to the occurrence of intramolecular hydrogen bonds, and thus strongly influences the opto-electronic and structural properties of the two polymers. PThDPPThF4 exhibits a stronger aggregation ability, a higher degree of crystallinity, a lower degree of paracrystallinity and an increased long-range order, which finally translates into a 20 times higher field-effect electron mobility. Finally, comonomer and side chain variations of DPP-based polymers are carried out for their potential use in thermoelectric investigations. Through the optimization of the polymerization conditions, a number-average molecular weight of 19.1 kg/mol is achieved for ThDPPTh-based polymers with single-oxygen side chains and F4 as comonomer. In addition, two ThDPPTh-based copolymers with biEDOT as comonomer are synthesized, which contain polar triethylene glycol (TEG) side chains as well as branched aliphatic side chains in different ratios. In summary, the economically efficient and ecologically green DAP method is demonstrated to be an efficient and versatile synthetic tool for copolymerizing TzDPPTz or ThDPPTh monomers bearing either aliphatic or polar side chains with either electron-rich or electron-deficient comonomers.
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