Dissertations / Theses: 'Carbocycle'

1

Marrison, Shaun. "Development of new radical cyclisation methodologies for carbocycle synthesis." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247637.

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2

Istrate, Florin-Marian. "Development of new transformations catalyzed by gold(I) complexes." Palaiseau, Ecole polytechnique, 2009. http://pastel.paristech.org/5595/01/Florin_Marian_ISTRATE_-_Ph.D._Manuscript.pdf.

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Dans les dernières années, les complexes d'or se sont avérés des excellents catalyseurs pour des nombreuses transformations homogènes impliquant l'activation des liaisons carbon-carbon multiples vis-à-vis de l'attaque des différents nucléophiles (Chapitre 1). Suite à la découverte par le Dr. Fabien L. Gagosz d'une nouvelle classe de catalyseurs cationiques d'or(I), cristallins, stables à l'air et très réactifs, ayant un groupement triflimide comme contre-anion (Chapitre 2), notre équipe s'est intéressée au développement de nouvelles transformations catalysées par ces complexes. Ce manuscrit présente une partie du travail effectué dans ce domaine qui a mené à la découverte de nouvelles méthodes pour la synthèse des différents dérivés hétéro- et carbocycliques, tels que les 4-alkylidène-1,3-dioxolan-2-ones (Chapitre 3), les 4-oxazolin-2-ones (Chapitre 4), les 2,5-dihydrofuranes (Chapitre 5), les pyrroles et les furanes (Chapitre 6), les esters de 1,3-butadièn-2-ol (Chapitre 7), les cyclopentènes (Chapitre 8) ou bien les 1,3-oxazinan-2-ones (Chapitre 9)

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3

Chambournier, Gilles. "Part I : Free radical cyclizations for carbocycle synthesis ;bPart II : diastereoselective synthesis of an enantiopure perhydroindole /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487951214941124.

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4

Phun, Lien Hoang. "Innovative approaches to carbocyclic and heterocyclic compounds using strained carbocycles." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47542.

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Natural products and small molecules play a major role in drug development. However, using natural products as a source of medicine comes with many challenges, such as lack of natural abundance and difficulty in isolation. Consequently, synthetic organic chemistry is a solution in order to access these compounds in usable quantities. However, synthetic chemisty comes with its own challenges such as efficiency, chemoselectivity, stereoselectivity and enantioselectivity. Therefore, synthetic tools that addresses these challenges are required solve these limitations. This thesis discusses new methodologies using strained carbocycles (cyclopropanes and cyclopropenes) as the reactive subunit for the construction of different carbocyclic and heterocyclic compounds. The homo-Nazarov cyclization of alkenyl and heteroaryl cyclopropyl ketones was used in order to construct cyclohexenones, cyclohexenols, heteroaryl ring-fused cyclohexenones, dihydrofurans, furans and furanones in a mild and efficient manner. Benzofused heteroaromatic compounds were achieved via the Lewis acid-catalyzed cycloisomerization of cyclopropene-3,3-dicarbonyls and furan-3-carboxylates. These heteroaromatic compounds can be applied to medicinal chemistry and material science.

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5

Haraguchi, Ryosuke. "Studies on Preparation of Functionalized Organozinc Reagents via Zinciomethylation." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215552.

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6

Dzwiniel, Trevor L. "Seven-membered carbocycle synthesis by cobalt-mediated [3 + 2 + 2] allyl/alkyne cycloaddition reactions and novel [5 + 2] cyclopentadiene/alkyne ring expansions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0033/NQ46833.pdf.

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7

Hsia, Kenneth Y. "Carbocycles from sugars." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260126.

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8

Joubert, Nicolas. "Synthèse et évaluation de nouveaux nucléosides ciblant l'hépatite C dans un système réplicon." Phd thesis, Université d'Orléans, 2006. http://tel.archives-ouvertes.fr/tel-00250329.

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Le virus de l'hépatite C est un problème de santé publique majeur, puisque 180 millions de personnes sont chroniquement infectées dans le monde, et sont susceptibles de présenter une cirrhose ou un cancer du foie. Un seul traitement a été approuvé, à base de Ribavirine et d'interféron alpha, mais il permet de traiter moins de 50 % des personnes infectées, et présente de nombreux effets secondaires. Devant ce constat, il parait urgent d'aboutir à une polythérapie plus adaptée. En dépit du succès des nucléosides en chimie antivirale, visant plusieurs enzymes clefs intervenant dans la réplication virale, peu d'entre eux ont été conçus pour viser l'ARN polymérase ARN dépendante nécessaire au VHC. Dans cette optique, de nouveaux dérivés carbocycliques de la Ribavirine, et des dérivés nucléosidiques du type 5-haloéthynyl- ou 5-(1,2-dihalo)vinyluracile, ont été synthétisés en utilisant deux méthodes : la réaction de Sonogashira et la cyclisation 1,3-dipolaire. Ce sont des outils puissants de la chimie organique qui permettent l'accès à de nouvelles structures nucléosidiques et la réalisation de modifications chimiques ultérieures. Les nouveaux composés ainsi préparés ont été testés pour leur activité antivirale.

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9

Joussot, Jessie. "Stratégies de synthèse d’un nouvel antipsychotique potentiel : cascades réactionnelles palladocatalysées : un outil puissant pour la synthèse de structures polycycliques complexes et hautement fonctionnalisées." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF016/document.

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Ces travaux de thèse ont permis dans un premier temps, d'aborder différentes voies de synthèse d'un nouvel antipsychotique potentiel (F17464) proposé par les laboratoires Pierre Fabre. Trois stratégies basées sur des synthèses convergentes ont été initiées. La première stratégie repose sur une étape clé de métathèse croisée, la seconde sur une réaction de Sonogashira et la troisième aborde une nouvelle méthodologie d'alkylation des chromones en position 3. Ces méthodes nous ont permis d'accéder à des intermédiaires de synthèse originaux, utiles pour préparer la molécule F17464 en respectant les contraintes industrielles.Dans un deuxième temps, différents types de molécules polycycliques complexes ont été synthétisés par cascades réactionnelles palladocatalysées. Une série de naphtalènes condensés a été préparée par réaction domino palladocatalysée issue de cyclocarbopalladations successives suivies d'une activation C(sp2)-H. Plusieurs types de cycles à sept atomes de carbone condensés ont été synthétisés en une seule étape, à partir de substrats faciles d'accès, via des cascades réactionnelles cyclocarbopalladations/activation C(sp2) ou C(sp3)-H.Finalement, des cyclooctatriènes et des fenestradiènes ont été obtenus à partir du même substrat,en une seule étape, via des réactions en cascade débutant par une cyclocarbopalladation 4-exodigsuivie d'un couplage de Stille puis d'une addition d'alcynes sur une triple liaison s'achevant par des réactions d'électrocyclisations. La température est le seul paramètre réactionnel qui diffère dans la synthèse de ces deux polycycles complexes, à partir du même substrat
This PhD thesis allowed us in the first part to develop different synthesic pathways to a new potential antipsychotic (F17464) invented by Pierre Fabre laboratories. Three strategies based on convergent syntheses are initiated. The key step of the first strategy is olefin cross metathesis. The second strategy rests on Sonogashira coupling and the third one involves a new methodology ofchromones alkylation in position 3. These methods allowed us access to novel synthetic intermediates, useful in the preparation of the F17464 molecule by following industrial confines.ln the second part, different types of polycyclic molecules were synthesized by palladium-catalyzed cascade reactions. A set of fused naphthalenes was prepared by palladium-catalyzed dominoreaction including cyclocarbopalladations followed by C(sp2)-H bond activation. Several types of fused seven-membered carbocycles were synthesized in a one-pot reaction from convenient substrates, via cascade reactions including cyclocarbopalladations followed by C(sp2 or sp3)-Hbond activation. Finally, cyclooctatrienes and fenestradienes were obtained also in a one-pot reaction from the same substrate via cascade reactions involving 4-exo-dig cyclocarbopalladation, followed by Stille coupling, alkyne addition onto a triple bond, finishing by electrocyclization reactions. Temperature is the only parameter that differs in the synthesis ôf the two complex polycycles starting from the same substrate

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10

Polomska, Marta Ewa. "Towards a total synthesis of mensacarcin." Doctoral thesis, [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=976248018.

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11

Mix, Stefan. "Synthese von Carbo- und Heterocyclen durch Ruthenium-katalysierte Kreuzmetathese Beitrage zur Katalysatorentwicklung /." [S.l.] : [s.n.], 2005. http://edocs.tu-berlin.de/diss/2004/mix_stefan.pdf.

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12

Stirner, Wolfgang. "Anellierungsreaktionen zu carbo- und heterocyclischen Ringsystemen Untersuchungen zur Regioselektivität und Stereochemie /." [S.l. : s.n.], 1999. http://www.ub.uni-duisburg.de/diss/diss9921/.

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13

Breukers, Stefanie [Verfasser]. "Asymmetrische organokatalytische Synthese von sechsgliedrigen Carbocyclen / Stefanie Breukers." München : Verlag Dr. Hut, 2013. http://d-nb.info/1045987808/34.

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14

Huang, Qinhua. "New Palladium-Catalyzed Approaches to Heterocycles and Carbocycles." Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2004. http://www.osti.gov/servlets/purl/835382-35f7N8/webviewable/.

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15

Maurette, Luc. "Synthèse de carbocycles à cinq et six chaînons." Toulouse 3, 2002. http://www.theses.fr/2002TOU30187.

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16

Blasco, Mata Jose Maria. "Silylated dienes as versatile precursors of trifluoromethylated carbocycles." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510930.

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17

Simonian, Houri. "Acyl radical mediated polyene cyclisations in synthesis." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307815.

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18

McCarter, Adam William. "New methods for the construction of selectively difluorinated carbocycles." Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=30287.

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The design and synthesis of geminal difluoromethylated compounds is extremely important owing to their unique biological properties, such as enzyme inhibition, pKa modulation and improving metabolic stability. However, efficient methods, starting from sustainable low cost starting materials, for the introduction of the gem-difluoromethylene group into cyclic molecules are still scarce. Work towards developing the de novo synthesis of difluorinated sugar analogues by using trifluoroethanol as an inexpensive building block is presented. The Saegusa-Ito cyclisation was utilised for the construction of selectively fluorinated carbocycles. Difluorinated silyl enol ether precursors were prepared in two synthetic steps from commercially available trifluoroethanol. Protection with diethylcarbamoyl chloride was followed by dehydrofluorination/lithiation, under cryogenic conditions, and the metalated enol carbamate generated in situ trapped with either a ketone or aldehyde electrophile. Following transacylation, the enolate species could be trapped with chlorotriethylsilane to afford silyl enol ethers in good yield. Cyclisations ensued smoothly under mild conditions. A combination of copper(I) chloride and Pd(OAc)2 in acetonitrile at 70 °C proved the most effective catalytic system. α,α-Difluoroketones were often isolated as mixtures of ketone and the corresponding hydrate; however, these mixtures could be efficiently dried in a vacuum oven to deliver pure ketones. The cyclisation of difluorinated enol acetals as alternative cyclisation mediators was investigated. These precursors were also synthesised in two steps from trifluoroethanol using cryogenic lithium based chemistry. Using a catalytic 1:1 mixture of 1,3-bis(2,6-diisopropylphenyl-imidazol-2-ylidene)gold(I) chloride and silver hexafluoroantimonate(V), the intramolecular carbocyclisation of difluorinated enol acetals has been achieved. Difluorinated enol acetals bearing a pendant alkene group can be cyclised and reduced in situ using tetrabutylammonium borohydride in one pot to form fluorinated diol motifs. Alternatively, the cyclisation of terminal alkynes allows for the concise synthesis of fluorinated pyran scaffolds. Both cyclisation processes can be performed under mild conditions allowing for the construction of complex difluorinated cyclic systems.

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19

Holt, David John. "Novel methods for the conversion of carbohydrates to carbocycles." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/30049.

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The 'chiron' approach to the synthesis of chiral target molecules from carbohydrates is now a well established component in the armoury of organic chemistry. A key element of this strategy is the range of methods available for the synthesis of cyclic compounds, which can include some or all of the carbons of the original carbohydrate (Chapter 1). The cyclopentaannulated sugar derivative 1, a product of intramolecular aldol condensation, was treated with N-bromosuccinimide (NBS), followed by activated zinc shot, to furnish a ca 4:1 mixture of cyclopentane derivatives 2 and 3 (Chapter 2). (Fig. 6078A). Ring closing metathesis has been applied to a series of substituted glucose derivatives, employing the Grubbs catalyst 4, to produce fused enantiomerically pure annulated sugars 5, containing five- to eight-membered carboyclic rings (Chapter 3). Copper(I) triflate catalyzed intramolecular [2+2] photocylization has also been studied as a method for carbohydrate annulation (Chapter 4). Photoannulation of 1,6-diene glucose derivatives leads efficiently to fused tetracyclic enantiomerically pure products, e.g.6. Investigations into the fragmentation of these annulated sugars, utilizing NBS and zinc methodology, in an attempt to synthesize enantiomerically pure carbocycles, are also described. (Fig. 6078B). As a continuation of work in the Jenkins group, directed towards the synthesis of a chiral taxoid from glucose, model studies were undertaken to test the viability of an enone to diene conversion, utilizing selenium chemistry (Chapter 5). Even though model studies showed this conversion to be successful, the enone 7 produced the diene 8 in a very poor yield (12%). Alternative methods for diene construction were investigated, including Wittig and Stille chemistry, with a limited amount of success. (Fig. 6078C).

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20

Standen, Patricia E. "Metathesis routes to carbocyclic frame works." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13204.

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The addition of allyl magnesium and allyl indium reagents to a key TBS protected norbornenyl building block, synthesised in 6-steps from commercially available 1,1-dimethoxy-2,3,4,5-tetrachlorocyclo-pentadiene, has been achieved providing the syn addition products with high diastereoselectivity. The subsequent exposure of the addition products to metathesis conditions, in the presence of ethylene, then provided cis fused [3.0.3]-carbocycles with very high regioselectivity, via a Ring Rearrangement Metathesis (RRM) transformation. The high level of regioselectivity is due to the rearrangement of the metathesis intermediates to give the more thermodynamically stable product This work has been expanded to include [2.2.2]-bicycles, addition of allyl magnesium and indium reagents to a key bicyclo[2.2.2]oct-5-en-2-one has been achieved, giving both diastereoisomers, separable by chromatography. The subsequent exposure of the addition products to optimised metathesis conditions, then provided cis fused [3.3.1] carbocycles with very high regioselectivity, via a RRM transformation. It was found that two possible cyclisation pathways occur under our reaction conditions; pathway (a) will yield a cis-fused [4.0.3]-carbocycle while pathway (b) will deliver the observed [3.3.1]-carbocycle.

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21

Finniear, Aled. "Asymmetric synthesis of chiral carbocyclic nucleosides." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283609.

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22

Agathocleous, D. C. "Synthesis of carbocyclic analogues of penicillin." Thesis, University of Huddersfield, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304428.

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23

Palmer, Christopher Francis. "Synthesis of carbocyclic analogues of clitocine." Thesis, University of Exeter, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277146.

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24

He, Mingzhu Schneller Stewart W. "Carbocyclic C-nucleosides derived from formycin." Auburn, Ala, 2008. http://hdl.handle.net/10415/1427.

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25

Hunt, Peter Alan. "Carbocyclic analogues of nikkomycins and polyoxins." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47482.

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26

Dossett, David Lawrence. "Alternatives to [4+1] carbocyclic annulations." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/101269.

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6-Carboethoxybicyclo [3.3.0] oct-6-en-2-one has been prepared by the intramolecular [4+1] cyclopentene annulation method. This compound and its precursor, 6-vinyl-6-carboethoxybicyclo[3.1.0]hexan-2-one were attained as the necessary standards for the investigation of the course of intramolecular Michael addition-alkylation sequence of l-phenylsulfonyl-6-carboethoxyocta-5,7-dien-2-one.
M.S.

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27

Mohr, Parveen Choudhary. "Transannular interactions in medium-ring carbocycles theoretical and experimental investigations /." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=984866213.

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28

Urbanietz, Gregor [Verfasser]. "Asymmetrische organokatalytische Synthesen vonhochsubstituierten sechsgliedrigen Carbocyclen und Heterocyclen / Gregor Urbanietz." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://d-nb.info/1059594005/34.

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29

Waldo, Jesse Page. "Iodine and palladium approaches to medicinally interesting heterocycles and carbocycles." [Ames, Iowa : Iowa State University], 2008.

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30

Chang, Weng Kun. "Development of Tandem Reaction for Synthesis of Highly Functionalized Carbocycles." Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:104067.

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Thesis advisor: James P. Morken
The Suzuki-Miyaura cross-coupling reaction is a common strategy for the formation of a new carbon-carbon bond in organic synthesis. However, intramolecular coupling of allylboron ester and aryl electrophiles has never been reported. Herein, Pd-catalyzed intramolecular cross-coupling of allylboronic pinacol ester and vinyl or aryl bromides is presented. Pt-catalyzed 1,2-diboration of 1,3-dienes give α-chiral bis-allylboronic esters, which can undergo diastereoselective additions to carbonyl electrophiles tethered to vinyl or aryl halides to generate a new allylboronic ester moiety. Under Suzuki coupling conditions, the allylboronic esters moiety and the vinyl bromides in the allylation products can cross-couple in an intramolecular fashion to afford highly substituted four-, five-, and six-membered rings with excellent yields and moderate diastereoselectivity
Thesis (MS) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry

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31

Worlikar, Shilpa Arvind. "Palladium-catalyzed and electrophilic cyclization approaches to carbocycles and heterocycles." [Ames, Iowa : Iowa State University], 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3320129.

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32

Archambeau, Alexis. "Cyclopropènes et métaux de transition synthèse de carbocycles et d'hétérocycles." Paris 6, 2013. http://www.theses.fr/2013PA066584.

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L’étude de la réactivité de cyclopropènes substitués dans diverses transformations catalysées par les métaux de transition, telles que la réduction de la double liaison et la formation de complexes métalliques de vinylcarbènes, est présentée dans ce manuscrit. Il a été montré que des amides, des esters et des cétones cyclopropéniques conjugués pouvaient subir des hydrogénations énantiosélectives par transfert, catalysées par des complexes chiraux du ruthénium(II), menant à des cyclopropanes tétrasubstitués avec d’excellents excès énantiomériques. Le transfert d’hydrogène est chimiosélectif puisque seule la double liaison cyclopropénique, dont la réactivité est exacerbée par la tension de cycle, est réduite. Les vinyl carbénoïdes de rhodium(II), résultant de l’ouverture de 3,3 diméthylcyclopropényl carbinols catalysée par le tétraacétate de dirhodium, ont pu être impliqués avec succès dans des réactions intramoléculaires d'insertion dans des liaisons C(sp3)-H. C'est ainsi que des carbocycles, des hétérocycles oxygénés et des composés bicycliques diversement substitués ont pu être synthétisés avec des rendements et des diastéréosélectivités élevés. Les résultats obtenus montrent que le 3,3 diméthylcyclopropène peut être avantageusement utilisé comme équivalent synthétique d’α diazocétone. L’étude de la réactivité des esters d’aryl cyclopropényl carbinyle a permis de découvrir un nouveau réarrangement, catalysé par les complexes de rhodium(II), menant à des méthylènecyclopropanes possédant une fonction ester d’énol, avec transfert de chiralité. Ces esters d’énol sont des intermédiaires intéressants pour accéder à des arylcyclopropanes substitués et fonctionnalisés
The investigation of the reactivity of substituted cyclopropenes in several transition metal-catalyzed reactions involving either the addition on the double bond or the ring-opening into vinyl metal carbenes is presented. It has been shown that conjugated cyclopropenyl amides, esters and ketones can undergo enantioselective transfer hydrogenation, catalyzed by chiral ruthenium(II) complexes, leading to tetrasubstituted cyclopropanes with excellent enantiomeric purity. The transfer hydrogenation occurs with high chemoselectivity in favour of the cyclopropene double bond due to the ring strain. The rhodium(II) vinyl carbenoids resulting from the ring-opening of 3,3 dimethyl-cyclopropenyl carbinols have been successfully involved in intramolecular C-H insertions. This method allows access to a variety of carbocycles, oxygen heterocycles and bicyclic compounds in excellent yields and with high diastereoselectivities. The investigation of the reactivity of aryl cyclopropenyl carbinyl esters had led to the discovery of a new rearrangement, catalyzed by rhodium(II) complexes, leading to methylenecyclopropanes bearing an enol ester with chirality transfer. These latter compounds are valuable intermediates to access a variety of substituted and functionalized arylcyclopropanes

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33

Burke, Mark Richard. "The use of cyclopentenones in the synthesis of novel carbocycles." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486045.

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4-Substituted cyclopentenones are key intermediates in the preparation of an array of highly functionalised cyclopentanes including most importantly in the project, carbocyclic nucleosides which display interesting biological activity. With the discovery that one stereoisomer exhibits generally more biological activity than the opposite stereoisomer and the escalating demand for new drugs to be enantiomerically pure, has led to the principal use ofenzymes in the development of routes to chiral carbocyclic nucleosides. The 1,4-diacetate was prepared via 3,4-diacetoh.)'cyclopentene using a modified method proposed by Deardorff and Mylesl . Following the limited success of this preparation, an alternative approach was adopted. An alternative approach to 1,4diacetoxycyclopentene used the photoaddition of singlet Oh.')'gen to the substrate cyclopentadiene, followed by protection. Elaboration ofthe 1,4-diacetate was attempted to afford various cyclopentenones via asymmetric hydrolysis, followed a photoaddition of methanol to the enone and a Mitsunobu reaction to afford the desired carbocyclic nucleoside. Selective deprotection of the silyl protecting group furnished a carbocyclic nucleoside analogue, which could be used for further elaboration to an array ofinteresting carbocyclic compounds. E),'olution ofthe project led to the synthesis ofseveral chir~l 4-alkyl-8-alkoxy-2-oxa-3aza- bicydo[3.3 .O]oct~3-en-6-Qnes. Further expansion of the tert-butyldimethylsilyl protected bicyclo-Qctenone to the bis-isoxazoline and symmetrical hydroxymethyl cyclopentanone diol were investigated with an array of chemical manipulations.

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34

Witherington, Jason. "Novel synthetic methods enabling the construction of biologically active compounds." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386942.

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35

Thorpe, Andrew John. "Synthetic approaches to novel adenosine analogues and the synthesis of potential antiviral agents." Thesis, University of Exeter, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357951.

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36

Mosley, Sylvester L. "Base-modified carbocyclic nucleosides as medicinal agents." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/27041.

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37

Bright, Steven. "Acid induced cationic rearrangements of carbocyclic compounds." Thesis, University of Canterbury. Chemistry, 1988. http://hdl.handle.net/10092/7597.

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This thesis examines fluorosulfonic acid as a reagent for use in organic synthesis. The acid strength of fluorosulfonic acid gives access to rearrangement products not available with weaker acids. The reaction of a selected series of benzyl carbinols with HSO₃F are reported. Reaction of 1-benzyl-2-methylcyclohexanol (1) gave cis-4a-methyl-1,2,3,4,4a,9a-hexahydrofluorene (2), while 1-benzyl -3-methylcyclohexanol (10) and 1-benzyl-4-methylcyclohexanol (11) were reduced to cis-1-benzyl-3-methylcyclohexane (12) and trans-1-benzyl-4-methylcyclohexane (13) respectively. [Diagram in thesis] 6-Benzylspiro[4.5]decan-6-ol (4) underwent a ring expansion to give the propellane, tetracyclo[7.4.4.0¹⁹.0²⁷]heptadeca-2,4,6-triene (5). Reaction of 1-benzyl-trans-decalin-1-ol (6) with HSO₃F gave the natural product (±)-9a-carba-14α-morphinan (7), while spiro[3-exobenzylbicyclo[2,2,1]heptan-3-endo-ol-2,1'-cyclopentane] (41) gave pentacyclo [9.7.0.0¹,¹⁴.0³,⁸.0⁹,¹⁴]octadeca-3,5,7-triene (42). The mechanism of rearrangement of 2-exo-benzylbicyclo[2.2.1] heptan-2-endo-ol (14) to 6-phenylbicyclo[3.2.1]oct-6-ene (16) was elucidated by the use of deuterium labeled substrates. Reaction of phenylethyl carbinols with HSO₃F afforded a route to bicyclic systems, for example 1-(2-phenylethyl)cyclohexanol (59) gave cis-1,2,3,4,4a,9,10,10a-octahydrophenanthrene (61) and spiro[cyclohexane-1,1-indane] (60), while 2-methyl-1-(2- phenylethyl)cyclohexanol (64) gave a mixture of cis- (65) and trans-4a-methyl-1,2,3,4,4a,9,10,10a-octahydrophenanthrene (66). [Diagram in thesis] Reaction of 1-(2-phenylethyl)-2,2,6-trimethylcyclohexanol (70) gave predominantly 1β,4aβ, 10 aβ-trimethyl-1,2,3,4,4a,9,10,10a octahydrophenanthrene (72) with a small amount of the 1a,4aβ,10aβ-trimethyl-isomer (73) while reaction of 2-exo-(2- phenylethyl)bicyclo[2,2,1 ]heptan-2-endo-ol (74) gave tetracyclo[10.2.1.0¹,¹⁰.0⁴,⁹]pentadeca-4,6,8-triene (75). Phenylpropyl carbinols provide an entry to spiro products. Reaction of 1-(3-phenylpropyl)cyclohexanol (85) gave spiro[cyclohexane-1,1-tetralin] (86), while 2-methyl-1-(3- phenylpropyl)cyclohexanol (87) gave trans-2'-methylspiro[ cyclohexane-1,1-tetralin] (88). [Diagram in thesis] 1,4-Diphenylbutan-1-ol (95) afforded 1-phenyl-1,2,3,4- tetrahydronapthalene (96) and 2,5-diphenylpentan-2-ol (97) gave an analogous product (98). 1,4-Di-(1-hydroxy-4-phenylbutan-1-yl)benzene (99) gave the two diastereoisomers of 1,4-di-(1,2,3,4-tetrahydronapth-1-yl)benzene (100), which on oxidation gave 1,4-di-(1-naphthyl) benzene (101). Fluorosulfonic acid has been shown to be a synthetic reagent for the generation of several novel spiro, reduction, cyclisation and rearrangement products not accessible under weaker acid conditions.

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38

Parry, David Mark. "Synthesis of some fluorinated carbocyclic nucleoside analogues." Thesis, University of Exeter, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305731.

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39

Shoberu, Karoline Adesola. "The biosynthesis and synthesis of carbocyclic nucleosides." Thesis, University of Exeter, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385737.

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40

Van, Eeden Nestor. "Synthesis of some potential antimicrobial carbocyclic compounds." Thesis, Cape Technikon, 1994. http://hdl.handle.net/20.500.11838/745.

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Thesis (M. Diploma in Technology (Chemistry))--Cape Technikon, 1994
Some naturally occurring compounds containing the naphtho [2,3 - c] pyran ring system have been found to be useful antibiotic agents and thus the laboratory synthesis ofthese compounds and their derivatives are of importance in the medical field. Their antibiotic and even antineoplastic activities are attributed to their potential to act as alkylating agents, via a bioreductive process. This thesis deals with studies directed towards the synthesis of some benzo [c] pyrans as these compounds also possess the correct structural configuration to undergo the bioreductive process, and act as alkylating agents to cellular nucleic acids. Chapter Two describes the synthesis 00,4 dihydro - 1,3 - dimethyl- IH - benzo - [cl pyran - 5,8 - quinone (13) by employing a base induced cyclization with potassium tertiary butoxide. This compound was proven to be biologically active against both Gram positive and Gram negative organisms. (±) (1R, 3R, 4R) - 3,4 - Dihydro - 4 - hyroxy -1,3 - dimethyl- 1H - benzo [e] pyran - 5,8quinone (17) and its 4 S diastereomer (18) were synthesized with cerium (IV) ammonium nitrate as the cyclizing reagent. Antimicrobial evaluation ofcompound (17) displayed inhibitory activity against both Gram positive and Gram negative organism growth. This is discussed in Chapter Three. In Chapter Four, the synthesis ofthe benzo analogue ofthe naturally occurring naphthopyran antibiotic, hongconin, is discussed. The synthetic route used for this synthesis could well be applied to synthesise hongconin.

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41

Giustra, Zachary Xavier. "Studies of BN-Isosteres of Carbocyclic Systems." Thesis, Boston College, 2018. http://hdl.handle.net/2345/bc-ir:108092.

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Thesis advisor: Shih-Yuan Liu
The first three chapters of this dissertation elaborate on certain facets of the isosteric relationship between different types of boron-nitrogen-containing heterocycles and the corresponding all-carbon compounds. In this vein, Chapter 1 describes selective photoisomerization of aromatic 1,2-dihydro-1,2-azaborines to BN-analogues of bicyclo[2.2.0]hexa-2,5-diene (Dewar benzene). In one instance, the photoisomer product was further derivatized into a series of disubstituted cyclobutanes through manipulations of the boron functionality. Chapter 2 discloses a combined experimental/theoretical mechanistic investigation of preliminary hydrogen release from the amine borane unit in a pair of BN-cycloalkanes. In Chapter 3, the kinetics of complementary dehydrogenation of the alkyl units in a BN-cyclohexene derivative are compared with those of related six-membered carbocycles. Chapter 4 treats with the separate subject of enantioselective silylation of glycerol by a catalytic strategy centered around reversible covalent binding of substrate hydroxyl groups
Thesis (PhD) — Boston College, 2018
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry

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42

Lau, Clifford James. "A study of several interesting carbocyclic molecules /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487584612166485.

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43

Saiegh, Tomas. "Activation de liaisons C-H de cyclobutènes et de sulfolènes. Application à la synthèse d’hétérocycles." Thesis, Université Paris sciences et lettres, 2020. http://www.theses.fr/2020UPSLS016.

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Le développement de méthodes de synthèse faisant intervenir la fonctionnalisation de liaisons C–H a permis, au cours des dernières années, la mise au point de nouvelles voies d’accès efficaces à des hétérocycles. Bien que de nombreux progrès aient été réalisés pour l’activation de liaisons C–H aromatiques en présence de complexes de métaux de transition, le champ d’application des méthodes impliquant l’activation de liaisons C–H vinyliques a été beaucoup moins illustré. C’est dans ce contexte que s’inscrivent les travaux réalisés au cours de la thèse qui portent sur la mise au point d’hétéro-annélations (4+2) impliquant l’activation de liaisons C(sp2)–H vinyliques de dérivés de l’acide cyclobutène-1-carboxylique. Cette stratégie a permis d’accéder, en présence de partenaires acétyléniques et de complexes de rhodium(III), à des cyclobuta[c]pyrones et -pyridones diversement substituées. Ces derniers composés peuvent être transformés en cyclobuta[c]pyridines, qui constituent des précurseurs d’orthoquinodiméthanes par ouverture du cycle à quatre chaînons, et peuvent être utilisés pour accéder à des composés polycycliques grâce à des réactions de Diels-Alder. De manière analogue, des dérivés de l’acide 3-sulfolène-3-carboxylique ont aussi été impliqués dans des hétéro-annélations (4+2) avec des alcynes, catalysées par les complexes de rhodium(III), pour synthétiser des pyrones, pyridones et des pyridines sulfoléniques. Ces derniers hétérocycles constituent d’autres précurseurs possibles d’ortho-quinodiméthanes par élimination chélotrope de dioxyde de soufre
In recent years, the development of synthetic methods relying on C–H bond functionalization has expandedthe reaction toolbox for the construction of heterocycles. Although considerable progress has been made in the fieldof aromatic C–H bond activation in the presence of transition metal complexes, the substrate scope of methods relyingon the activation of vinylic C(sp2)−H bonds has been much less investigated. In this context, the work carried out duringthis PhD thesis has been devoted to the development of (4+2) heteroannulation reactions relying on the activation ofvinylic C(sp2)−H bonds in cyclobuten-1-ylcarboxylic acid derivatives. In the presence of acetylenic partners andrhodium(III) complexes, this strategy has allowed access to diversely substituted cyclobuta[c]pyrones and -pyridones.These latter compounds can be transformed into cyclobuta[c]pyridines which are precursors of orthoquinodimethanes, by opening of the four-membered ring, that can be involved in the synthesis of polycyclic compounds thanks to Diels-Alder reactions. Accordingly to a similar approach, 3-sulfolene-3-carboxylic acid derivatives were also involved in rhodium-catalyzed (4+2) heteroannulations with alkynes to access sulfolenyl pyrones, pyridones and pyridines. These latter heterocycles are also ortho-quinodimethanes precursors by cheletropic elimination ofsulfur dioxide

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44

Ahmad, Sajjad. "One-pot tandem reactions for the stereoselective synthesis of functionalised carbocycles." Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3524/.

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A one-pot, two step tandem process involving an Overman rearrangement and a ring closing metathesis reaction has been utilised for the efficient synthesis of various cyclic allylic trichloroacetamides from simple allylic alcohols. Various methods were then investigated for the allylic oxidation of a carbocyclic amide using TBHP along with different transition metals such as Pd, Se, Mn and Cr. This was required for the synthesis of the important building blocks for the construction of structurally diverse antiviral and anticancer carbocyclic nucleosides and natural products. The oxidation of (1S)-N-(cyclohexenyl)trichloroacetamide was then studied leading to the preparation of two diol analogues in excellent stereoselectivity. The cyclohexene derivative was also stereoselectively functionalised using Upjohn dihydroxylation conditions or by a directed epoxidation/hydrolysis sequence of reactions to generate two aminocyclitols, the enantiomer of dihydroconduramine C-1 and dihydroconduramine E-1 in excellent stereoselectivity. In addition to this, a one-pot tandem process involving a substrate-directed Overman rearrangement and ring closing metathesis reaction was developed for the stereoselective synthesis of a functionalised carbocyclic allylic trichloroacetamide. The functionalised carbocyclic amide was employed in the successful synthesis of a syn-(4aS,10bS)- phenanthridone framework using a Pd-catalysed cross-coupling reaction. Stereoselective epoxidation and dihydroxylation of the syn-(4aS,10bS)-phenanthridone was then investigated leading to the preparation of new analogues of 7-deoxypancratistatin. Attempts were also made to use the functionalised carbocyclic amide in the total synthesis of the Amaryllidaceae alkaloid (+)-γ-lycorane. Further studies were then investigated to expand the scope of the one-pot tandem process to include heterocyclic derived substrates. This led to a seven-membered carbocyclic amide, which has been modified to create a diastereomeric core of balanol.

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45

Mehta, Saurabh. "Palladium-catalyzed and electrophilic cyclization approaches to important heterocycles and carbocycles." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3389126.

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46

Afshari, Mohammad. "Quelques aspects de la réactivité ambiphile de carbocycles à trois chaînons." Aix-Marseille 3, 1992. http://www.theses.fr/1992AIX30044.

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Ce travail est consacre a l'etude des deux aspects de la reactivite ambiphile de la structure cyclopropanique. La premiere partie porte sur le comportement electrophile d'acylcyclopropanes qui ont ete opposes a l'allyltrimethylsilane en presence d'acide de lewis. Cette etude nous a permis de mettre en evidence un aspect nouveau de la reactivite du cyclopropane monoactive. L'identification des produits nous a fait postule l'intervention d'un intermediaire cyclopropylcarbinyle forme apres l'addition d'une premiere molecule d'allylsilane sur le carbonyle. Suivant la structure de l'acylcyclopropane, cet intermediaire reagit soit par addition bimoleculaire d'une deuxieme molecule d'allylsilane sur le carbocycle, soit par attaque direct sur le carbone porteur de la charge positive formelle. Dans une deuxieme partie, pour etudier l'aspect nucleophile de la reactivite du microcycle, tout en conservant l'homogeneite du modele, nous avons synthetise des silylmethylenecyclopropanes. Le reactif nucleophile ambident genere a partir de ces composes par reaction avec l'ion fluorure (tbaf) a ete oppose a des aldehydes. Les produits obtenus consistent en un melange d'alcools a structure methylenecyclopropanique et cyclopropenique. L'ensemble de ces resultats peut d'interpreter par l'intervention partielle d'un anion silicate pentacoordine

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47

Isakovic, Ljubomir. "Synthesis of the carbocyclic core of CP-225,917." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38208.

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A new method for the synthesis of the [4,3,1] carbocyclic core of the squalene synthase and farnesyl transferase inhibitor CP-225,917 is developed. The key step relies on the [6+4] cycloaddition between a tropone and a cyclopentadiene. This reaction proceeds with excellent regio- and stereoselectivity and allows rapid and convergent access to the polycyclic core of the molecule.
In the course of this work, it was discovered that the cycloaddition process is significantly accelerated in presence of the catalytic amount of ZnCl2. This is the first example of Lewis acid catalyzed [6+4] tropone cycloaddition.
Introduction of other functional groups towards the synthesis of CP-225,917 skeleton is described. The key to the success of this strategy is a position selective Baeyer-Villiger oxidation on the tricyclic cycloadduct. This reveals functionality which can be used to elaborate the C9 side-chain and incorporate the bridgehead olefin.*
*Please refer to dissertation for diagrams.

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48

Streete, Isla. "Towards the synthesis of carbocyclic sialic acid analogues." Thesis, Heriot-Watt University, 2003. http://hdl.handle.net/10399/421.

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49

Abbasali, Qasim Azad. "Early transition metal complexes of membered carbocyclic rings." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364135.

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50

Popescu, Anne. "Racemic carbocyclic nucleosides and their anti-viral activity." Lund : Lund University Chemical Center, 1995. http://books.google.com/books?id=5vhqAAAAMAAJ.

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Dissertations / Theses on the topic 'Carbocycle'

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