Dissertationen: „1,3-dipolar cycloaddition reaction“

1

Kafley, Saurav. „Synthesis and 1, 3 -dipolar cycloaddition reaction of N-phenyl £ chlora nitrone“. Thesis, University of North Bengal, 2010. http://hdl.handle.net/123456789/1419.

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2

Chakraborty, Bhaskar. „Studies of 1, 3 Dipolar cycloaddition reactions with N- cyclohexyl Nitrones“. Thesis, University of North Bengal, 1995. http://hdl.handle.net/123456789/768.

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3

Toh, Ophilia Ndi. „Synthesis Towards Fulminic Acid and Its Derivatives in 1, 3-Dipolar Cycloaddition Reactions“. Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etd/1982.

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A new approach to fulminic acid cycloadditions has been developed. At reduced temperatures, fulminic acid is generated in situ and undergoes 1, 3-diploar cycloaddition reactions with dipolarophiles to form isoxazolines and/or its dimers. This procedure represents a novel, safe general method for the one-step generation of fulminic acid, which complements existing potentially explosive protocols.

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4

Bala, Kason. „1, 3-dipolar cycloaddition reactions in aqueous media and investigations into solid phase ether synthesis“. Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397163.

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5

Rai, Neelam. „Greener synthesis and 1, 3-dipolar cycloaddition reactions of a amino nitrones and studies of biological activities of the cycloadducts“. Thesis, University of North Bengal, 2017. http://ir.nbu.ac.in/handle/123456789/2663.

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6

Draghici, Cristian. „Discovery of a Novel Ring Fragmentation Reaction; Efficient Preparation of Tethered Aldehyde Ynoates and N-Containing Heterocycles;Radical Addition Approach to Asymmetric Amine Synthesis“. ScholarWorks @ UVM, 2009. http://library.uvm.edu/dspace/bitstream/123456789/224/1/Draghici%20Disssertation.pdf.

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7

Kamm, Philipp Willi. „Understanding of lambda-orthogonal photo-induced reaction systems“. Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/234293/1/Philipp%20Willi_Kamm_Thesis.pdf.

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Using light as an energy source allows chemical reactions to be carried out with high precision in time and space. In time, because light can be switched on and off, in space, because light can be highly focussed. Further, different colours of light can be used to activate different reactants individually, even when they are present in the same reaction mixture. Herein, a system of two light-sensitive molecules was developed, which react completely sequence-independently with UV or visible light. The wavelength-dependence as well as the influence of chemical-physical parameters on such reactions were investigated in-depth.

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8

Chandanshive, Jay Zumbar <1983&gt. „Regiocontrolled Synthesis of Pyrazole Derivatives Through 1,3-Dipolar Cycloaddition Reaction And Synthesis of Helicene-Thiourea based and Polymer Supported Soos's Catalyst for Asymmetric Synthesis“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5826/1/Chandanshive_JAY_ZUMBAR_Thesis.pdf.

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In first part we have developed a simple regiocontrolled protocol of 1,3-DC to get ring fused pyrazole derivatives. These pyrazole derivatives were synthesized using 1,3-DC between nitrile imine and various dipolarophiles such as alkynes, cyclic α,β-ketones, lactones, thiocatones and lactums. The reactions were found to be highly regiospecific. In second part we have discussed about helicene, its properties, synthesis and applications as asymmetric catalyst.Due to inherent chirality, herein we have made an attempt to synthesize the helicene-thiourea based catalyst for asymmetric catalysis. The synthesis involved formation of two key intermediates viz, bromo-phenanthrene 5 and a vinyl-naphthalene 10. The coupling of these two intermediates leads to formation of hexahelicene.

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9

Schmitt, Gérard. „Réactions de l'hydrofluoroborate d'un composé de Reissert sur divers alcenes : Compétition entre cycloaddition dipolaire-1,3 et cycloaddition de Diels-Alder“. Besançon, 1987. http://www.theses.fr/1987BESA2041.

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10

Berndt, Christian. „Bildungstendenz und Reaktionen von α-Azidoalkoholen“. Doctoral thesis, Universitätsbibliothek Chemnitz, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-112553.

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Gegenstand der vorliegenden Arbeit ist die Synthese von α-Azidoalkoholen durch die Reaktion von aliphatischen sowie aromatischen Aldehyden mit Stickstoffwasserstoffsäure. Dabei stellt sich ein Gleichgewicht ein, dessen Lage durch die Ermittlung der Gleichgewichtskonstanten quantitativ bestimmt wird. In jedem Fall besteht die Möglichkeit, den α-Azidoalkohol in der Gleichgewichtsmischung zu charakterisieren und teilweise gelingt die Isolierung der reinen α-Azidoalkohole bei tiefen Temperaturen sowie deren Charakterisierung mittels Tieftemperatur-NMR-Spektroskopie. Die Ausgangsaldehyde für die Synthese der α-Azidoalkohole besitzen elektronenschiebende oder elektronenziehende Substituenten oder sind prochiral oder besitzen funktionelle Gruppe für intramolekulare Reaktionen. Die Titelverbindungen werden mit Cyclooctin im Sinne einer 1,3-dipolaren Cycloaddition abgefangen oder mit Carbonsäurechloriden in die entsprechenden Ester der α-Azidoalkohole überführt. Das nur aus theoretischen Arbeiten bekannte Formylazid wird erstmals aus den α-Azidoalkoholen durch Oxidation hergestellt und in Lösung vollständig charakterisiert. Es werden zudem zahlreiche Alternativsynthesen für Formylazid erfolgreich durchgeführt.

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11

Bose, Rajib Kumar. „1, 3 -Dipolar cycloaddition of * -Amino nitrone“. Thesis, University of North Bengal, 1993. http://hdl.handle.net/123456789/760.

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12

Danielsson, Jakob. „Stereoselective Nucleophilic Additions to Aldehydes and Synthesis of α-Amino-β- Hydroxy-Esters“. Licentiate thesis, KTH, Organisk kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-95467.

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This thesis deals with the development of new reaction methodology as well as stereochemical investigations. The first part concerns the investigation of 1,2- and merged 1,2- and 1,3- asymmetric induction in Mukaiyama aldol additions to α-heteroatom and α,β- heteroatom substituted aldehydes respectively. In particular, the unexpected 1,2-syn selectivity obtained in the addition of sterically hindered nucleophiles to α-chloroaldehydes is examined, and an explanation for the observed stereochemical trends is proposed. The second part describes the development of a novel entry to α-amino-β- hydroxy esters by a 1,3-dipolar cycloaddition reaction of aldehydes and azomethine ylides, generated by thermolysis of aziridines. The third part deals with our efforts to develop a novel entry to vicinal all- carbon quaternary centers, based on an intramolecular domino Heck- carbonylation reaction using tetrasubstituted olefins.
QC 20120611

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13

Richter, Sebastian. „Neue binäre CN-Verbindungen sowie Vorläufersubstanzen von monomerem C3N4“. Doctoral thesis, Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-155547.

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Gegenstand dieser Arbeit sind Versuche zur Synthese neuer binärer Kohlenstoffnitride im Allgemeinen und von C3N4-Vorläuferverbindungen im Speziellen. Hierbei werden v. a. die Herstellung und die Eigenschaften organischer Polyazide beschrieben, die aufgrund ihrer Gefährlichkeit durch zahlreiche Folgereaktionen in weniger brisante Moleküle überführt werden mussten. Als Derivatisierungsreaktionen kamen hierbei beispielsweise die 1,3-dipolare Cycloaddition mit Norbornen und Cyclooctin, die STAUDINGER-Reaktion mit verschiedenen Phosphinen sowie die Aza-WITTIG-Reaktion zum Einsatz. Es konnten dabei u. a. zehn Röntgeneinkristallstrukturen erhalten und als Strukturbeweis aufgeführt werden. Zahlreiche hochaufgelöste Massenspektren sowie Elementaranalysen und NMR-Daten bestätigten außerdem alle neu erhaltenen Strukturen. Einen weiteren Schwerpunkt dieser Arbeit stellen Versuche zur Synthese von monomerem C3N4 dar, dessen Herstellung zwar nicht gelang, für dessen Bildung allerdings neue Möglichkeiten ausgehend von verschiedenen Edukten beschrieben werden. Darüber hinaus wurden bereits bekannte Moleküle auf ihre Eignung als C3N4-Vorläufer untersucht, wobei z. B. durch Azid-Addition an Nitrilgruppen unerwartete neue Produkte erhalten werden konnten.

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14

Goodall, Glenn William. „Utilising 1 ,3-dipolar cycloaddition chemistries in the synthesis of linear and hyperbranched polymers“. Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.630448.

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15

Yalcinkaya, Hatice. „Studies On The Reaction Of Acyl Phosphonates With Aldehydes In The Presence Of Proline“. Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610359/index.pdf.

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Acyl phosphonates are interesting precursors for the synthesis of biologically active compounds. In the first part, the acyl phosphonates are synthesized starting from the corresponding acyl chloride. The acyl chlorides are converted into acyl phosphonates by using trialkylphosphites. The reaction of acyl phosphonates with aldehydes in the presence of proline furnished not the suggested aldol products via proline catalyzed aldol reaction but bicyclic products via one pot tricomponent 1,3-dipolar cycloaddition reaction. The formation of the bicyclic compound was suggested as followed
The formation of iminium salt of proline with aldehyde followed by decarboxylation furnished azomethine. The 1,3-dipolar cycloaddition of the formed azomethine with carbonyl group of acyl phosphonate afforded substituted hexahydro pyrrolo oxazole structures. 1,3-Dipolar cycloaddition forms the basis of the most preparatively useful procedures for the synthesis of five-membered heterocycles. One example is the 1,3-dipolar cycloaddition of azomethine ylides (from imines) and alkenes, which allows the stereoselective synthesis of pyrrolidines or proline derivatives.

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16

Compain-Batissou, Cudel Muriel. „SYNTHESE DE NOUVELLES QUINONES HETEROCYCLIQUES PAR APPLICATION DES REACTIONS DE CYCLOADDITIONS DE DIELS-ALDER ET 1,3-DIPOLAIRE. EVALUATION IN VITRO DE LEUR ACTIVITE SUR TOXOPLASMA GONDII“. Phd thesis, Université Claude Bernard - Lyon I, 2007. http://tel.archives-ouvertes.fr/tel-00281991.

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La toxoplasmose est une anthropozoonose ubiquitaire causée par Toxoplasma gondii. Malgré de nombreuses recherches, l'arsenal thérapeutique reste très restreint. L'objectif des travaux présentés dans ce mémoire est la synthèse de carbazolequinones et l'évaluation de leur efficacité sur T. gondii. Les carbazolequinones naturelles comme les calothrixines ont des propriétés antiparasitaires et cytotoxiques. La synthèse de para- et ortho-quinones de type benzo-, isoxazolo- et triazolo-carbazolequinones a été réalisée par application des réactions de cycloaddition [4+2] ou 1,3-dipolaires régiosélectives. La stratégie de synthèse à partir de dipolarophiles monobromés permet en effet, d'accéder sélectivement au régioisomère souhaité. Les attributions de structure des régiosiomères ont été confirmées par RMN 1H NOE et par une étude des corrélations 1H -13C HMBC. Concernant l'évaluation biologique in vitro, les composés inhibent la croissance de T. gondii comme la sulfadiazine et la pyriméthamine, avec une cytotoxicité sur les cellules myélomonocytiques THP1. Aucun des composés synthétisés n'inhibent la PNP, enzyme clé de la voie de sauvetage des purines, seule voie d'accès pour le parasite aux bases puriques. L'inhibition de la croissance de T. gondii par nos composés n'est pas liée directement liée à l'inhibition de la PNP.

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17

Lucas, Rodrigues Leona. „Advanced photochemical reactions induced by visible light“. Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/235925/1/Leona%2BLucas%2BRodrigues%2BThesis%283%29.pdf.

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Nature utilizes the energy of light for chemical transformations such as photosynthesis or the visual systems in human eyes, where wavelengths from predominantly high energetic UV to harmless visible light are consumed by the respective chromophores. Therefore, the herein presented thesis focusses on developing photoreactive molecules responsive to visible light to ensure minimal harm in form of photo-bleaching or degradation to molecules, polymers or materials via three major reaction pathways: light induced ligation, bond-cleavage/rearrangement and isomerization reactions. Here, a particular focus lays on the development of novel and advanced reactions to establish versatile platforms.

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18

HU, JIEYU. „COPPER(I) CATALYZED EXO-SELECTIVE [CN+C+CC] 1,3-DIPOLAR CYCLOADDITIONS and STUDIES TOWARDS THE TOTAL SYNTHESIS OF KAITOCEPHALIN“. Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1269965489.

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19

Plefka, Oliver. „1,3-Dipolare Cycloaddition von N2O an hochreaktive Mehrfachbindungen“. Doctoral thesis, Universitätsbibliothek Chemnitz, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-70667.

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In der vorliegenden Arbeit wird über 1,3-dipolare Cycloadditionen mit Lachgas (N2O) unter milden Reaktionstemperaturen (≈ RT) berichtet. N2O ist ein sehr unreaktives 1,3-dipolares Reagenz. Bisher in der Literatur durchgeführte 1,3-dipolare Cycloadditionen mit N2O benötigten immer sehr drastische und gefährliche Reaktionsbedingungen (bis zu 300°C und 500 atm.). Dabei entstanden nach einer (postulierten) einleitenden 1,3-dipolaren Cycloaddition von N2O an Olefine oder Alkine immer nur stickstofffreie Reaktionsprodukte. Durch den Einsatz von hochreaktiven Cycloalkinen als 1,3-Dipolarophile konnten erstmals 1,3-dipolare Cycloadditionen mit N2O bei deutlich milderen Bedingungen (–25°C bis +60°C) als den bisher bekannten durchgeführt werden. Dabei war es mit Cyclooctin und Cycloocten-5-in erstmals möglich, stabile und vollständig charakterisierbare Reaktionsprodukte zu erhalten, die alle drei Atome des addierten N2O-Moleküls enthalten. Mit 4,5-Didehydro-2,3,6,7-tetrahydro-3,3,6,6-tetramethylthiepin konnte sogar erstmals ein alpha-Diazoketon durch 1,3-dipolare Cycloaddition von N2O erhalten und dieses bei –25°C NMR-spektroskopisch untersucht werden. Diese alpha-Diazoketone entstehen aus der elektrocyclischen Ringöffnung der entsprechenden 1,2,3-Oxadiazole welche aus der Cycloaddition von N2O und dem eingesetzten Cycloalkin stammen. Mit alpha-substituierten Cyclooctinen konnten auch 1,3-dipolare Cycloadditionen mit N2O bei milden Temperaturen durchgeführt werden, um stickstofffreie Reaktionsprodukte zu erhalten.

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20

Lobo, Marcio Marçal. „Síntese regiosseletiva de Dideoxinucleosídeos e 3(5)-Trifluormetil-1H-pirazóis de interesse farmacológico“. Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4276.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
This work reports the synthesis of a series of 29 new 1-(3-aryl-4,5-dihydroisoxazol-5-yl)methyl-4-trihalomethylpyrimidin-2(1H)-ones which have high pharmacological interest, since they are similar to natural and synthetic nucleosides. These compounds were obtained from 1,3-dippolar cycloaddition reaction between the 1-allyl-(6-aryl)-4-trihalomethylpyrimidin-2(1H)-ones and different benzonitrile oxides, obtained from the selected oximes of general formula ArCH=NOH (where Ar = Ph, 4-FC6H4, 2-MeC6H4, 4-MeC6H4, 2-MeOC6H4, 4-MeOC6H4, styryl, 2-OHC6H4 e 4-OHC6H4). The reaction conditions employed were highly regioselective, because it was observed the formation of only 3,5-substituted isomer by both NMR spectral analysis and X-ray diffractometry. The compounds were obtained in good yields (58 99%) and were purified from recrystallization or by column chromatography on silica gel. Some the obtained compounds showed antineoplastic activity in vitro against different tumor cell lines. Additionally, three new N3-substituted pyrimidinic dideoxynucleoside analogues were prepared, which were obtained in good yields (88 97%) from the reaction of N-allyl-2-methylthiopyrimidin-4(3H)-one and some of the benzonitrile oxides mentioned above. The reactions for the formation of N3-substituted nucleoside still require optimization. This thesis also described the regiochemisty controled synthesis of two series of pyrazoles, named 5(3)-aryl-3(5)-trifluoromethyl-(1H-pyrazol-1-yl)benzenesulfonamides, structural analogues of Celecoxib (14 examples), where aryl = Ph, 4-FC6H4, 4-MeC6H4, 4-MeOC6H4, 4-ClC6H4, 4-BrC6H4, furan-2-yl, from the cyclocondensation reaction between 4-aryl-1,1,1-trifluoromethyl-4-methoxy-3-buten-2-ones and 4-hydrazinobenzenosulfonamide hydrochloride. The isolation of either isomer depended on the initial pH medium, where the alkaline pH favored the isolation of the 1,5-substituted isomer at yields of 73 99% and the reaction conducted in acid pH favored the isolation of the 1,3-substituted isomer, with yields of 77 94%. This study also allowed the isolation and spectroscopic characterization of a novel series of 3-aryl(heteroaryl)-5-hydroxy-5-trifluoromethyl-(1H-pyrazol-1-yl)benzenesulfonamides (7 examples) in yields of 75 97% with interesting anti-inflammatory and antinociceptive activities in vivo.
Esta tese apresenta a síntese de uma série de 29 moléculas inéditas de 1-(3-aril-4,5-diidroisoxazol-5-il)metil-4-trialometilpirimidin-2(1H)-onas que possuem alto interesse farmacológico, visto que são análogos a nucleosídeos naturais e sintéticos. Esses compostos foram obtidos a partir de reação de cicloadição 1,3-dipolar entre as 1-alil-(6-aril)-4-trialometilpirimidin-2(1H)-onas e diferentes óxidos de benzonitrila, obtidos a partir das oximas selecionadas, de fórmula geral ArCH=NOH (onde Ar = Ph, 4-FC6H4, 2-MeC6H4, 4-MeC6H4, 2-MeOC6H4, 4-MeOC6H4, Estiril, 2-OHC6H4 e 4-OHC6H4). As condições reacionais empregadas mostraram-se altamente regiosseletivas, uma vez que, por análise dos espectros de RMN e por difratometria de raios-X, observou-se a formação apenas do isômero 3,5-substituído. Os compostos foram obtidos em bons rendimentos (58 99%) e puderam ser purificados a partir de recristalização ou através de coluna cromatográfica em sílica gel. Alguns dos compostos obtidos apresentaram atividade antineoplásica in vitro frente a diferentes linhagens de células tumorais. Também estão apresentados 3 novos análogos nucleosídeos pirimidínicos N3-substituídos, obtidos em bons rendimentos (88 97%) a partir da reação da N-alil-2-metiltiopirimidin-4(3H)-ona e de alguns óxidos de benzonitrila acima citados. As reações para a formação dos nucleosídeos N3-substituídos ainda necessitam de otimização. Nesta tese também está descrito o controle regioquímico para a síntese de duas séries de pirazóis, nomeados 5(3)-aril-3(5)-trifluormetil-(1H-pirazol-1-il)benzenosulfonamidas, análogos estruturais do Celecoxib (14 exemplos), onde aril = Ph, 4-FC6H4, 4-MeC6H4, 4-MeOC6H4, 4-ClC6H4, 4-BrC6H4, fur-2-il, a partir da reação de ciclocondensação entre 4-aril-1,1,1-trifluormetil-4-metóxi-3-buten-2-onas e o cloridrato de 4-hidrazinilbenzenosulfonamida. O isolamento de um ou outro isômero dependeu do pH inicial do meio, onde o pH básico favoreceu o isolamento do isômero 1,5-substituido com rendimentos de 73 99% e a reação conduzida em pH ácido favoreceu o isolamento do isômero 1,3-substituído, com rendimentos de 77 94%. Este estudo também possibilitou o isolamento e caracterização espectroscópica de uma série inédita de 3-aril(heteroaril)-5-hidróxi-5-trifluormetil-(1H-pirazol-1-il)benzenosulfonamidas (7 exemplos) em rendimentos de 75 97%, com interessante atividade anti-inflamatória e antinociceptiva in vivo.

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21

Cosson, Fanny. „Synthèse d’analogues carbonés de la Ribavirine pour leurs activités antivirales“. Thesis, Cergy-Pontoise, 2014. http://www.theses.fr/2014CERG0687/document.

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La Ribavirine est un analogue nucléosidique de la guanosine constitué d'un ribose et d'un noyau triazole. Cet antiviral, synthétisé en 1970, possède une activité contre différents virus comme le virus respiratoire syncytial chez les enfants en détresse respiratoire, les virus des hépatites B et E, ainsi que contre certains cancers et leucémies. Elle est surtout connue pour son utilisation dans le traitement de l'hépatite C, en combinaison avec l'Interféron. Cependant, l'efficacité de cette thérapie est limitée à certains génotypes du virus et les effets secondaires résultants sont nombreux. C'est pourquoi il est nécessaire de trouver d'autres analogues actifs contre l'hépatite C et moins toxiques afin d'offrir un traitement aux 170 millions d'individus atteints de cette maladie chronique et pouvant évoluer vers des cirrhoses et des cancers du foie. Par une méthodologie d'alcynylglycosylation médiée à l'indium suivie d'une cycloaddition 1,3 dipolaire, des C-nucléosides analogues de la Ribavirine ont été synthétisés. L'un deux, SRO-91, a montré une activité antivirale comparable à celle de la Ribavirine vis-à-vis de l'ARN polymérase du virus de l'hépatite C. L'objectif de cette thèse est donc de synthétiser d'autres C-nucléosides analogues sur le modèle de SRO-91. Des modifications ont été effectuées autant sur le ribose que sur le noyau triazole. Concernant les transformations du ribose, nous nous sommes intéressés à la position C2', notamment en introduisant une quaternisation avec différents groupements (CH3, CF3, F …) ou bien en désoxygénant cette position. Cette thèse décrit les différentes stratégies explorées pour la synthèse de plusieurs de ces C-nucléosides dont les activités antivirales seront étudiées ultérieurement
Ribavirin is a nucleosidic analogue of guanosine composed of a ribose and a triazole ring. This antiviral compound, synthesized in 1970, exhibits an activity against a broad-range of viruses such as respiratory syncytial virus in respiratory distress children, hepatitis B and E viruses as well as some cancers and leukemia. It is especially known for its use in hepatitis C treatment in combination with Interferon. However, the efficiency of this therapy is limited to a few genotypes of the virus and leads to numerous side effects. Therefore, finding new efficient and less toxic analogs is necessary to treat the 170 million individuals that are chronically infected and at risk of developing cirrhosis and liver cancer. Thanks to a methodology of indium mediated alcynylglycosylation followed by a 1,3-dipolar cycloaddition, C-nucleosides analogs of Ribavirin have been synthesized. Among them, SRO-91, showed a comparable activity to Ribavirin towards hepatitis C virus ARN polymerase. This thesis' objective is to synthesize other C-nucleosides analogs based on SRO-91 model. Modifications have been made on the triazole ring as well as on the ribose. In regards to the ribose transformations, we have been interested into the C2' position, in particular by introducing a quaternisation with different moieties (CH3, CF3, F …) or by deoxygenating this position. This thesis describes the different strategies explored for the synthesis of some of these C-nucleosides whose antiviral activities will be studied later

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22

Torssell, Staffan. „Amino Aacohols : stereoselective synthesis and applications in diversity-oriented synthesis“. Licentiate thesis, KTH, Chemistry, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-315.

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This thesis is divided into three separate parts with amino alcohols as the common feature. The first part describes the development of a novel three-component approach to the synthesis of α-hydroxy-β-amino esters. Utilizing a highly diastereoselective Rh(II)-catalyzed 1,3-dipolar cycloaddition of carbonyl ylides to various aldimines, syn-α-hydroxy-β-amino esters formed in high yields and excellent diastereoselectivities. This methodology was also applied in a short enantioselective synthesis of the C-13 side-chain of Taxol.

The second part of the thesis describes a total synthesis of D-erythro- Sphingosine based on a cross-metathesis approach to assemble the polar head group and the aliphatic chain.

The last part deals with the application of amino alcohols as scaffolds in a diversity-oriented protocol for the development of libraries of small polycyclic molecules. The design of the libraries is based on the iterative use of two powerful ring-forming reactions; a ring-closing metathesis and an intramolecular Diels-Alder reaction, to simultaneously introduce structural complexity and diversity.

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23

Sultan, Nisrine. „Preparations selectives de derives du 7-oxanorborna-2,5-diene : utilisation comme formes masquées de composés acetyleniques“. Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112132.

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En vue d’effectuer des préparations sélectives de composés hétérocycliques, une étude de la synthèse et de la réactivité de 7-oxanorborna-2,5-diènes portant des groupes électroattracteurs différents sur les positions 2 et 3 a été réalisée. Ces composés sont des formes masquées de composés acétyléniques dissymétriques.Dans un premier temps, nous avons optimisé une nouvelle méthode de synthèse sélective d’acétylènedicarboxylates dissymétriques par mono-transestérification d’acétylènedicarboxylates de dialkyle symétriques avec des alcools en présence de la lipase de Candida rugosa. Cette méthode nous a permis d’obtenir les diesters dissymétriques avec de bons rendements et une haute sélectivité a priori inattendue.Dans un second temps, nous avons développé des synthèses régiosélectives de dérivés de l’acide 7-oxanorborna-2,5-diène-2,3-dicarboxylique selon deux stratégies. Dans une première approche, une réaction de Diels-Alder intramoléculaire entre un furane et un composé acétylénique reliés par une agrafe siliciée a été réalisée, suivie d’une coupure des liaisons Si-C. Cette cycloaddition [4+2] s’effectue uniquement en présence de MeAlCl2 avec des rendements moyens. Dans certains cas, la coupure des liaisons Si-C conduit aux diesters désirés. Dans une deuxième approche, une mono-saponification d’oxanorbornadiène-2,3-dicarboxylates de dialkyle a permis d’accéder régiosélectivement à des monoacides et des réactions de couplage avec des amines ou des alcools ont conduit sélectivement à des dérivés présentant deux groupes électroattracteurs différents.Dans une dernière partie, nous avons effectué la préparation régiosélective de 3-pyrrolines par cycloaddition [2+3] d’un ylure d’azométhine suivie d’une réaction de rétro-Diels-Alder à partir des 7-oxanorbornadiènes comportant deux groupes électroattracteurs différents. La préparation aisée de 3-pyrrolines condensées non décrites dans la littérature a été obtenue par formation inattendue d’un motif succinimide dans le cas des amidoesters.En conclusion, il apparaît que la présence du groupe éthyle en tête de pont des 7-oxanorborna-2,5-diènes semble suffisante pour contrôler la régiosélectivité de ces cycloadditions
In order to selectively prepare heterocyclic compounds, a study of the synthesis and reactivity of 7-oxanorborna-2,5-dienes with different electron-withdrawing groups on the 2 and 3 positions was performed. These compounds are masked forms of unsymmetrical acetylenic compounds. At first, we have optimized a new method for the selective synthesis of unsymmetrical diesters by transesterification of symmetrical dialkyl acetylenedicarboxylates in the presence of Candida rugosa lipase. This unexpectedly highly selective method allowed us to obtain unsymmetrical acetylenedicarboxylates in good yields.In a second part, we have developed a regioselective synthesis of 7-oxanorborna-2,5-diene-2,3-dicarboxylic acid derivatives according to two strategies. In one approach, an intramolecular Diels-Alder reaction between a furan and an acetylenic compound connected by silicon-containing tethers was performed, followed by a cleavage of the Si-C bonds. This [4+2] cycloaddition was carried in the presence of a Lewis acid, only MeAlCl2 gave the expected product and so in moderate yields. In most cases, the cleavage of Si-C bonds leads to the desired diesters. In a second approach, a mono-saponification of dialkyl oxanorbornadiene-2,3-dicarboxylates provided access regioselectively to mono-acids and coupling reactions with amines or alcohols selectively led to poly-functionalized products containing two different electron-withdrawing groups.In the last part, we have regioselectively prepared 3-pyrrolines by [2+3] cycloaddition of an azomethine ylide to 7-oxanorbornadienes bearing electroattracting groups followed by a retro-Diels-Alder reaction. An easy synthesis of previously unknown condensed 3-pyrrolines was obtained by formation of an unexpected succinimide pattern from amidoesters. In conclusion, it appears that the presence of an ethyl group on the bridgehead carbon atom of 7-oxanorborna-2,5-dienes seems sufficient to control the regioselectivity of these cycloadditions

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Ferroud, Clotilde. „Étude de la réaction de Diels-Adler intra et intermoléculaire sous haute pression : application à la synthèse stéréosélective d'alcaloïdes de l'indole du groupe des yohimbanes“. Paris 6, 1986. http://www.theses.fr/1986PA066023.

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Le schéma de synthèse repose sur une unité bicyclique, précurseur direct des unités (d,e) du squelette pentacyclique. Cet intermédiaire est basé sur une réaction de Diels-Alder sous haute pression, utilisant la cycloaddition de diènes de structure donneur-accepteur 1,4 avec une lactone insaturée comme diénophile. La synthèse du système pentacyclique est exposée à partir de cet intermédiaire clé.

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CHU, WEI-ZHANG, und 朱煒章. „The study of 1, 3-dipolar cycloaddition reaction of 3-arylsydnone-4-carbonitrile oxides and their properties“. Thesis, 1987. http://ndltd.ncl.edu.tw/handle/53347898816217429334.

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Takahito, Kasahara. „The development of a 1,3-dipolar cycloaddition reaction with 1,5-dimethyl-3-phenyl-6-oxoverdazyl radical“. 2007. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=788897&T=F.

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林孟嬌. „1,3-Dipolar Cycloaddition of 5-Methoxy-1-methy1-3-oxidopyridinium Synthesis of Phenyl Tropone“. Thesis, 1994. http://ndltd.ncl.edu.tw/handle/50274909882126174641.

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碩士
高雄醫學大學
藥學研究所
82
1,3-Dipolar cycloaddition of l-methyl-3-oxidopyridinium (8) has been the subject of much synthetical interest. However, the application is quite limited because of insufficient 1,3-dipolar reactivity of the betaine (8), the reaction succeeds with olefinic dipolarophiles containing a strongly electron-withdrawing group, but fails with other olefins. In order to increase the reactivity of the betaine several attempts has been made, and replacement of the methyl group on the nitrogen of (8) by electronwithdrawing substituent as in the betaine (10) was reported to be effective. The synthesis of phenyl tropone based on the 1,3-dipolar reactivity of 5-methoxy-l-methyl-3-oxidopyridinium (1) is described.

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Ze-PeiDong und 董澤霈. „Studies of electronic structure of sydnones and their reaction via [3+2] dipolar cycloaddition by molecular orbital calculation“. Thesis, 2011. http://ndltd.ncl.edu.tw/handle/43550157922650478632.

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