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1
Silva, Raquel Sofia de Oliveira Nunes da. "Phthalocyanine-sulfonamide conjugates-synthesis and biological activity." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22842.
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Doutoramento em Química<br>O uso inapropriado de antibióticos no tratamento de doenças infeciosas tem
levado a um aumento da resistência de diversos microrganismos patogénicos,
o que apresenta atualmente um problema de saúde pública e tem motivado a
procura de estratégias alternativas para o controlo destes microrganismos. Por
outro lado, a procura de novas moléculas ou novas combinações de moléculas
para o combate ao cancro é um assunto em constante desenvolvimento.
Na presente dissertação descreve-se o trabalho desenvolvido para a obtenção
de conjugados de ftalocianina–sulfonamida e a avaliação da atividade dos
novos compostos como fotossensibilizadores. Os conjugados foram
idealizados com o intuito de promover um possível efeito sinérgico das suas
unidades constituintes, nomeadamente propriedades antitumorais e/ou
antimicrobianas. Para tal, desenvolveram-se métodos de síntese de
sulfonamidas e de conjugados de ftalocianina–sulfonamida. Algumas das
ftalocianinas obtidas foram testadas como fotossensibilizadores na eliminação
fotodinâmica de células tumorais e de bactérias, utilizando-se as linhas
celulares de carcinoma de células escamosas orais (HSC3) e de
queratinócitos orais (HaCaT), e as bactérias Escherichia coli (Gram-negativo)
Staphylococcus aureus (Gram-positivo) como modelos biológicos. Os
resultados destes estudos revelaram que as ftalocianinas estudadas são muito
promissoras como fotossensibilizadores para a inativação fotodinâmica de
células tumorais e de microrganismos. Por outro lado, foi também
desenvolvido um ensaio enzimático para avaliar a atividade dos novos
compostos como inativadores da enzima anidrase carbónica, em particular a
isoforma IX que se encontra sobre-expressa em células tumorais e é bem
conhecida como reguladora do pH em processos de hipoxia e acidose
metabólica.
Este estudo vem dar mais um passo no conhecimento científico das
ftalocianinas e evidencia o potencial das ftalocianinas sulfonadas na
perspetiva do controlo de infeções e da tumorogénese.<br>The inappropriate use of antibiotics in the treatment of infections has led to an
increase in the resistance of several pathogenic microorganisms, which
represents a major public health issue and triggered the search for novel
antimicrobial drugs. On the other hand, the search for new molecules or new
combinations of molecules for the fight against cancer is a subject in constant
development.
The present dissertation describes the work developed to obtain
phthalocyanine–sulfonamide conjugates and the biological evaluation of these
compounds as photosensitizers. These conjugates were designed to explore
their antimicrobial and/or antitumor properties.
Methods for the synthesis of sulfonamides and phthalocyanine–sulfonamide
conjugates were developed. Some of the phthalocyanines obtained were tested
as photosensitizers for the photodynamic inactivation of tumor cells and
bacteria. HSC3 oral squamous cell carcinoma, HaCaT 'normal' keratinocytes,
and the bacteria Escherichia coli (Gram-negative) and Staphylococcus aureus
(Gram-positive) were used as biological models.
The phthalocyanines studied proved to be very promising to be considered in
future studies in the perspective of the photodynamic inactivation of tumor cells
and microorganisms. On the other hand, an enzymatic assay was also
developed to evaluate the activity of the compounds obtained as inactivators of
the enzyme carbonic anhydrase, in particular the IX isoform that is
overexpressed in tumor cells and is well-known as pH regulator in processes of
hypoxia and metabolic acidosis.
This study represents a contribution to the application of phthalocyanines, and
in particular sulfonated phthalocyanines, in the control of infections and
tumorigenesis.
2
Hall, Brady. "Synthesis, Characterization, and Polymerization of Sulfonamide Based Bifunctional Monomers." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1471349342.
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Garcia, Cristina. "Synthesis of ring fused 2-pyridones." Thesis, Umeå universitet, Kemiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-102704.
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Kiss, Emily. "Diasterodivergent synthesis of fused ring systems." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:37545702-38f9-4bb5-a233-69a296387792.
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Introduction: We envisioned using phase transfer catalysis (PTC) to develop asymmetric carba-6p- electrocyclisations. We believed that the configurational lability of 6p systems could be reduced by constraining them within a ring system. Results and Discussion: En route to the synthesis of a starting material for the transannular electrocyclisation reaction, we noticed that a 5-5-3 fused ring system had formed, in one step, from a linear precursor and as a single diastereomer. We synthesised both geometric isomers of the starting materials, and unexpectedly, the E or Z isomers cyclised to form different products under different reaction conditions. We further investigated the 5-5-3 system, generating substrate scope and computationally and experimentally exploring the mechanism. Conclusion: In one step we have constructed three carbon-carbon bonds, up to five contiguous stereogenic centres and all as a single diastereomer. We have synthesised 15 examples and have probed the mechanism experimentally and computationally. We have also investigated asymmetric examples of this reaction.
5
Hubbard, Jeremiah W. "Novel synthesis of 3,4-fused indoles." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=2209.
Full textAbstract:
Thesis (M.S.)--West Virginia University, 2001.<br>Title from document title page. Document formatted into pages; contains xi, 70, 76 p. : ill. Includes abstract. Includes bibliographical references (p. 67-70).
6
Cartwright, Matthew William. "Highly functionalised fused heterocycle synthesis from fluoropyridines." Thesis, Durham University, 2006. http://etheses.dur.ac.uk/2622/.
Full textAbstract:
Current approaches to drug discovery tends to involve the rapid analogue synthesis and testing of small, focused libraries of low molecular weight, structurally similar "drug-like" molecules, often based around heterocyclic core scaffolds. If some desired activity is shown by a compound, elaboration can give higher activity and more favourable pharmiokinetic properties. As this "lead generation" stage of drug development has been identified as a major bottleneck in the drug pipeline process, there is a great demand for methodology detailing the synthesis of highly functionalised heterocyclic compounds. Our approach involves the sequential nucleophilic aromatic substitution of highly fluorinated pyridines, in an efficient and flexible manner, to furnish a range of novel, functionalised polycyclic systems.
7
Rodger, Robert. "Fused ring systems in natural product synthesis." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/27645.
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On the instigation of A/Prof C. S. P. McErlean I investigated the rapid synthesis of fused ring compounds by a key polyene cyclisation.
Chapter 1 sets the scene by highlighting deficiencies in literature syntheses of selected fused-ring compounds, where synthetic strategies are often suboptimal. In particular, the scarcity of reported syntheses involving a direct cyclisation method is noted.
Chapter 2 discusses the taiwaniaquinoids and previous synthetic approaches including McErlean group efforts which delivered the non-natural stereochemistry. A method to produce the desired trans stereochemistry of ()-taiwaniaquinone G was developed. Attempts to apply this methodology to a divergent synthesis of the taiwaniaquinoids are detailed.
Chapter 3 extends this strategy to the attempted synthesis of compounds with a greater number of rings: the dasyscyphins, pelorol, atomarianone B and disidein. The successful partial cyclisation and subsequent full cyclisation of two farnesylarenes was reported. Larger architectures remain an elusive goal.
Chapter 4 discusses efforts in the synthesis of a different class of fused-ring compounds: the marine polycyclic ethers. The application of newer methodologies to the synthesis of the polycyclic ethers is described, however this did not lead to a viable strategy to these compounds.
8
Allwein, Shawn Paul. "Iterative strategies toward the synthesis of fused ether ring systems and the synthesis of fused ether containing natural products." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/280230.
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A highly efficient and general approach to fused ether ring systems has been presented. The approach couples stereoselective C-glycoside forming reactions with subsequent annulations. C-glycosides were formed from glycals through an oxidation and carbon-carbon bond forming sequence. Annulations involving a two step methylenation/enol ether-olefin ring closing metathesis or a single flask, acid mediated cyclization/elimination proved to be efficient tribenzyl- D-glucal (95), [4.4.0] and [4.5.0] bicyclic enol ethers (194, 200, 204) were stereoselectively generated in 2-4 steps in good overall yields (53%, 57%, and 39% respectively). Iteration resulted in the stereoselective formation of tricylic enol ethers (240, 241). In addition, our C-glycoside approach was applied to the synthesis of fused ether containing natural products. A formal synthesis of (±)-hemibrevetoxin B (2) was achieved by intercepting Mori's intermediate ( 278) in 21 steps and 3.8% overall yield. The C-glycoside approach to fused ethers was also demonstrated in the synthesis of halichondrin B's model compounds, bicycle 374 and tricycle 383. Subsequent fragmentation of 383 resulted in bicyclic alcohol 384 which correlates to the C,23-C,38 subunit of halichondrin B (8).
9
Steele, Rory G. "Synthesis of fused cyclic ethers : towards the synthesis of hemibrevetoxin B." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363594.
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Flores, Jose Luis Castrejon. "The chemical synthesis of sulfonamide metabolites and their role in drug hypersensitivity." Thesis, University of Liverpool, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511083.
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11
Sengpracha, Waya. "Synthesis of biologically active indole-fused heterocyclic derivatives." Department of Chemistry - Faculty of Science, 2005. http://ro.uow.edu.au/theses/279.
Full textAbstract:
New synthetic routes to 1,2- and 2,3-fused indoles with seven- or eight-membered rings have been developed in this project, with the longer term aim of assessing their biological activity. Approaches to such fused indole derivatives were accessed via free radical cyclisation from 1- or 2-substituted indole derivatives with haloacetamide precursors. Using 1-substituted indole derivatives with haloacetamide functionalites, free radical cyclisation reactions gave fair yields of the indole- and dihydroindole-fused eight membered ring derivatives. Using 2-substituted indole derivatives with haloacetamide functionalities, prepared in turn by a palladium-mediated cyclisation of N-substituted indoles followed by hydrolysis and subsequent decarboxylation, free radical cyclisation afforded the 7,12-dihydro-indolo[3,2-d]benzazepin-6(5H)-one (Paullone) system in fair yields. A novel synthetic approach to a bis-indole fused seven-membered ring system was developed based on an N-substituted spirooxindole rearrangement. The spiro-indolinols obtained from partial amide reduction underwent rearrangement to give the bis-indole fused seven-membered ring derivatives 270 and 271 under acidic conditions. Antimicrobial activity of the indole fused eight-membered ring systems was evaluated. The compound 5,14-dihydro-10-methoxy-5-methoxy-5-methyindolo[2,1-d][1,5]benzodiazocin-6-one 186c showed by far the most potent antibacterial activity (against Staphylococcus aureus), while 5,14-dihydro-5-(4-methoxybenzyl)indolo[2,1-d][1,5]benzodiazocine-6-one 186d showed good in vitro antimalarial activity against both drug resistant and drug sensitive strains of Plasmodium falciparum. These two compounds represent novel structural leads for such activities.
12
Pink, Jennifer Helen. "Synthesis of fused lactams via N-acyliminium ions." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242373.
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Hitchings, G. J. "The synthesis of fused heterocycles containing bridgehead-nitrogen." Thesis, University of York, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383838.
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Rickwood, Martin. "Synthesis and reactivity of bridgehead [1,5]-fused imidazoles." Thesis, University of Edinburgh, 1986. http://hdl.handle.net/1842/14280.
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Bobba, Viharika. "SULFONAMIDE DERIVATIVES AS TUBULIN INHIBITORS AND SELECTIVE ANTI-TRYPANOSOME AGENTS – DESIGN, SYNTHESIS & BIOLOGICAL EVALUATION." Cleveland State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=csu1468241198.
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Nower, Peter. "Synthesis of a novel dinucleotide analog containing a conformationally restricted sulfonamide internucleotide linkage." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22784.
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There are some examples where conformational restriction has been introduced into nucleotides with the sole purpose of increasing the thermodynamic stability of the duplex or triplex between the modified oligonucleotide and its complement. This thesis explored the hypothesis of incorporating a cyclopropane moiety into the internucleotide linkage. This research demonstrates the successful synthesis of a novel cyclopropanated sulfonamide dinucleotide 19.(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE MAI)<br>This novel molecule has been synthesized by reacting an $ alpha, beta$ unsaturated phenylselenoyl nucleotide derivative 7 with an active methylene sulfonamide nucleotide 17 under Michael addition conditions. Binding studies concerning the cyclopropanated sulfonamide dinucleotide 19 are pending.
17
Tatsuya, Nakano. "Synthesis and Functionalization of Fused Aromatic Ring-layered Compounds." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199330.
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Leow, M. L. "Synthesis and pyrolysis of fused cinnolines related to dibenzobutalene." Thesis, University of Sunderland, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355596.
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Hayes, R. "The synthesis of 5,6,7- and 7,7-fused azepine systems." Thesis, University of Salford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381852.
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Wang, Hong. "Total synthesis and structure of [beta], [beta]-fused metallocenoporphyrins /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.
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Jackson, P. Mark. "Diels-Alder reactions of heterocyclic fused α-pyrones". Thesis, Loughborough University, 1991. https://dspace.lboro.ac.uk/2134/27733.
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The chemistry of heterocyclic analogues of orthoquinodimethane is reviewed. Benzothieno[2,3-c]pyran-3-ones and the isomeric [3,2-c]pyranones are stable analogues of benzothiophene-2,3-qyinodimethane. When heated with alkynes they undergo Diels-Alder reaction to give, after loss of carbon dioxide, dibenzothiophenes.
22
Chen, Yiding. "Synthesis of sulfur-containing organic compounds : sulfones, sulfonamides and benzoisothiazoles." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:92038d85-0597-4db0-8e56-0a32c671a655.
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This thesis documents the development of novel methodologies for access to sulfur-containing compounds, including sulfones, sulfonamides and benzoisothiazoles. <b>Chapter 1</b> provides an overview of the applications and the synthesis of sulfonyl-containing compounds. A comprehensive introduction to the development of sulfur dioxide surrogates and their applications in transition metal-catalysed organic chemistry is given. <b>Chapter 2</b> describes the development of a one-step copper(I)-catalysed sulfonylative Suzuki-Miyaura cross coupling reaction. A wide range of aryl and alkenyl boronic acids are coupled with aryl and alkenyl iodides to give the corresponding sulfones. A two-step one-pot sulfination/derivatisation method was also developed, allowing access to compounds including β-hydroxy sulfones, sulfonamides and sulfonyl fluorides. <b>Chapter 3</b> illustrates a one-step copper(II)-catalysed sulfonamide synthesis using boronic acids, amines and SO2. Various aryl and alkenyl boronic acids as well as amines and anilines are compatible, including active pharmaceutical ingredients such as amoxapine and desloratadine. <b>Chapter 4</b> details an aryne-based selective formation of substituted benzoisothiazoles. Different substitution pattern of the aryne precursor and the thiadiazole are employed, with the target heterocycles being obtained in good to excellent yields. <b>Chapter 5</b> summarises the research and the future work. <b>Chapter 6</b> documents the experimental procedures and data.
23
Xu, Jin. "Synthesis of novel sulfonamide-based calpain inhibitors and their potential as anti-tumor agents." View the abstract Download the full-text PDF version, 2007. http://etd.utmem.edu/WORLD-ACCESS/Xu/2007-028-Xu.pdf.
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Thesis (M.S. )--University of Tennessee Health Science Center, 2007.<br>Title from title page screen (viewed on July 28, 2008). Research advisor: Dr. Isaac O. Donkor, Ph.D. Document formatted into pages (xii, 80 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 65-80).
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Otter, Carl A. "The synthesis and coordination chemistry of mixed donor pyridine/phenol and pyridine/sulfonamide ligands." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246241.
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Kucukdisli, Murat. "Asymmetric Synthesis Of Chiral Camphor Fused Pyridine Type Novel Organocatalysts." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610790/index.pdf.
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Chiral pyridines as organocatalysts have been used in asymmetric organic synthesis in recent years. The asymmetric synthesis of camphor fused pyridine type novel organocatalysts were perfomed starting from cheap and easily available natural (+)-camphor. Using camphor fused pyridine skeleton, six organocatalysts 29, 32, 33, 38, 40, and 41were successfully synthesized. The first four nucleophilic and Lewis base catalysts 29, 32, and 33 are different P-oxides and P,N-dioxides which were tested in allylation of aldehydes via allyltrichlorosilane. L-proline amide 38 and D-proline amide 40 can be named as secondary amine catalyst. They were tested in direct aldol reaction between acetone and aromatic aldehydes in aqueous medium. Final group of catalyst is hydrogen bonding type catalyst which is thiourea based 41.
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Naoe, Saori. "Synthesis of Fused-Ring Compounds through Gold-Catalyzed Cascade Reactions." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215495.
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Tice, Nathan Charles. "THE SYNTHESIS, STRUCTURE, AND REACTIVITY OF SOME ORGANOMETALLIC-FUSED HETEROCYCLES." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_diss/297.
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The synthesis, structure, and reactivity of some organometallic-fusedheterocycles were studied. This work was divided into three parts: first,thiapentalenyl tricarbonyl manganese complexes [Mn(CO)3{??5-SC7H3-1,3-(R)2}]were synthesized employing thiation on diacyl precursors; second, attempts toform the 5,5-fused ring pyrrole analogs to the thiapentalenyl complexes led to theformation of various amine and imine ligands and manganese complexes, but notthe desired ring-closed pyrroles; third, reductive amination on a ferrocenylmonoaldehyde substrate led to the formation of di(N-(ferrocenylmethyl))-Nmethylamineand its cyanoborane and cyanoborohydride analogs.Isolation of the desired thiapentalenyl manganese complexes wasaccomplished by first forming 1,2-diacylcyclopentadienes (fulvenes), convertingto the corresponding thallium salts [Tl{1,2-C5H3(COR)2}] employing thalliumethoxide, transmetallating with [Mn(CO)5Br], and ring closing using either P4S10or Lawesson's Reagent. Ring closure from the diacylmanganese complexes[Mn(CO)3{??5-1,2-C5H3(COR)2}] gave air stable thiapentalenyl complexes inmoderate to good yield and was tolerable to a variety of functional groups (aryl,arylacetyl, t-butyl). In the cases where 1,2-diarylacetyl complexes wereemployed, the isolated products were "quinoidal". While ring closure on thecorresponding diacylrhenium tricarbonyl complexes was not feasible, it wasobserved that these quinoidal thiapentalenyl structures could be formed on aruthenium Cp* moiety using the arylacetyl fulvenes.Various keto-amines or enol-imines could be formed from the 1,2-dibenzoyl fulvene employing primary amines (R = H, Me, OH, OMe). In thepresence of a reducing agent, neither reduction nor ring closure was observedfor any of the cases investigated. Formation of the corresponding manganesetricarbonyl complex for the methyoxyimine case was accomplished by reaction ofthe enol-methoxyimine with thallium ethoxide and then transmetallating with[Mn(CO)5Br]. Reaction of this keto-imine complex with various reducing agentsdid not lead to the desired 5,5-fused ring pyrrole complex but to reduction to thecorresponding alcohol.Diferrocenylmethyl methylamine complexes were obtained by reaction offerrocene monoaldehyde with ferrocenylmethyl methylamine in the presence of amild reducing agent (NaCNBH3). Isolation under anhydrous conditions gave theunexpected cyanoborohydride salt, di(N-(ferrocenylmethyl))-N-methylammoniumcyanoborohydride. Aqueous work-up gave the corresponding free amine.Conversion of the cyanoborohydride salt to the corresponding cyanoborane,di(N-(ferrocenylmethyl))-N-methylammonium–cyanoborane, was accomplishedby refluxing the cyanoborohydride salt in THF.
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Geraghty, Paul Bythell. "Studies towards the synthesis of fused N-Heterocyclic carbene precursors." Thesis, University of Canterbury. Chemistry, 2013. http://hdl.handle.net/10092/8197.
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This thesis describes the preparation of a various NHC ligands with five and six-membered rings, different fused aromatic cores and the subsequent synthetic development of their complexation of with Ag, Ru and Pd. The investigation and preparation of these compunds was with the intention of exploring their chemical and physical properties. The synthesis of the NHC ligands proved to be difficult, but analysis and characterisation of the side products from the reactions helped to establish successful synthetic methodologies. In both the five and six-membered research conducted a common attribute was established of a pyrid-2-yl substituent at the 1 position or both the 1 and 3 positions, thus providing new NHC ligands to investigate.
The organic syntheis of the research focused on two NHC ligand functionalites, five and six membered rings. The six memerbered rings focused on 1H-perimidine as the core unit and the design of both bidentate and tridentate NHC ligands to mimic the structural binding relationship of 2,2’- bipyridine (bpy) and 2,2’:6’2”-terpyridine (tpy) with various metal salts. The synthesis of the bpy analogues was achieved in good overall yields with minimal synthetic challenges. However, the tpy analogue was unable to be realised due to time constraints and problems associated with its synthesis. The five membered NHC ligands synthesised were to investigate the physical effects of systematically increasing the size of its aromatic core. The main focus of the research was on the phenanthrene imidazole NHC ligands. This was investigated due to the minimal research that has been conducted on this core unit and NHC-complexes. Synthesis of the two-bidentate NHC ligands with an imidazole head group and fused phenanthrene backbone were completed, but this was with a picolyl substituent at the 1 position rather than the pyrid-2-yl substituent. This failure to isolate this product was attributed to steric influences. Pyrene-fused-imidazole NHC ligands were also investigated and pyrene offers a NHC core that hasn’t been investigated previously. However, synthesis and isolation of the NHC ligands proved to be difficult and was associated with the poor solubility of the NHC ligands.
The organometallic NHC synthesis was studied extensively with the main focus on establishing appropriate conditions to give a NHC complex. The main metal investigated was ruthenium as subsequent NHC complexes were expected to have potentially interesting properties such as luminescence. The synthesis of a perimidine and phenanthrene NHC ruthenium complexes have not been isolated before, thus giving new NHC complexes. Many different synthetic routes were attempted to synthesise a perimidine NHC ruthenium complex. However, this proved difficult due to associated higher reactivity of the carbene carbon of perimidine with a new side product as a result of this research. The phenanthrene NHC complex synthesis suffered due to time constraints but potential methodology for their synthesis is stated.
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Ladwa, Mitesh Mohan. "A radical approach towards the synthesis of fused nitrogen heterocycles." Thesis, University of Aberdeen, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430405.
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A literature review of the chemistry of homolytic aromatic substitution is presented with particular emphasis to the formation of fused heterocyclic systems. A series of five-membered spirocyclic 5-azaoxindole-ring systems have been synthesised by generating an alkyl radical that underwent an intramolecular radical cyclisation at the 3-positon of a pyridine ring and was followed by oxidation giving rise to a mix of fused pyridine ring systems. However, numerous problems were encountered with this investigation, not least the stability of the alpha brominated carbonyl radical precursor, consequently an alternative protocol was investigated. Bromine was therefore introduced at the 3-position of the heteroaromatic ring. Generation of the radical followed by a 1,5 radical translocation, an intramolecular radical cyclisation followed by oxidation furnished the required fused ring systems. Synthesis of the 5-azaoxindole systems was also shown to proceed in good yield in the presence of a 2-fold excess of AIBN and only poorly when 1.2eq was used using this method. The methodology was successfully extended demonstrating that cyclisation of an alkyl radical is regioselective at the 2-positoin of the pyridine over the 4-position providing access to a variety of 4-azaoxindole systems. It was also shown that radical cyclisation into the pyrimidine ring is a feasible process although in rather poor yield. As a final challenge to probe the generality and utility of homolytic aromatic substitution into heterocyclic ring systems six-membered fused ring systems were investigated. This investigation resulted in the formation of a range of six-membered nitrogen heterocycles in excellent yield and provided access to the core ring system of the natural alkaloid sesbanine.
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Duffy, Kevin James. "Studies on the synthesis and reactivity of fused 3,4-isoxazoles." Thesis, University of Edinburgh, 1993. http://hdl.handle.net/1842/13734.
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This thesis is concerned with the synthesis of various fused, 3,4-isoxazoles by the thermal cyclisation of 2-nitroaryl and 2-nitroheteroaryl acetic acid derivatives and the exploitation of the uses of these compounds in heterocyclic synthesis by their reduction to afford 2-aminoaryl and heteroaryl ketones followed by the annulation of these latter derivatives. Heating solutions of 2-(3-nitropyrid-2-yl)propanedioate esters under reflux in inert solvents afforded isoxazolo[4,3-b]pyridine-3-carboxylate derivatives. The successful application of this novel synthesis on a large scale was crucially dependent on the physical removal of the corresponding alcohol component from the reaction mixture. The thermal cyclisation of various 2-substituted 2-(3-nitropyrid-2-yl)ethanoates was also examined and in the case of cyano derivatives afforded the anticipated isoxazolo[4,3-b]pyridines but was less successful for substrates containing keto groups. 2-(3-Nitropyrid-2-yl)ethanoate failed to cyclise to afford the parent isoxazolo[4,3-b]pyridine. Evidence is presented for the involvement of ketene intermediates in these thermal cyclisation reactions. Reduction of the isoxazol[4,3-b]pyridine-3-carboxylate derivatives gave either 2-(3-aminopyrid-2-yl)-2-hydroxyethanoate or 2-(3-aminopyrid-2-yl)-2-oxoethanoate derivatives depending on the substrate, the former compounds being converted into the latter by oxidation with manganese dioxide. Annulation of the 2-(3-aminopyrid-2-yl)-2-oxoethanoates produced then gave a variety of substituted 1,5-napthyridin-2(1H)-one derivatives. The chemical transformations of these new 1,5-napthyridine derivatives was also briefly examined. 1,7-Napthyridin-2(1H)-one derivatives were also prepared by a similar sequence of reactions commencing with the thermal cyclisation of diethyl 2-(3-nitropyrid-4-yl)propanedioate to give ethyl isoxazolo[3,4-c]pyridine-3-carboxylate followed by reductive ring opening of the latter and subsequent annulation of ethyl 2-(3-aminopyrid-4-yl)-2-oxoethanoate so produced.
31
Widerberg, Staffan. "Synthesis of ring-fused 2-pyridones with potential antibiotic properties." Thesis, Umeå universitet, Kemiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-139400.
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Matak, Andrija. "Synthesis and spectroscopic analysis of 4'-amino and 4'-sulfonamide chalcone derivatives and ultrastructural effects of 4'-sulfonamide boronic acid chalcone on Eimeria papillata sporozoites in vitro /." Link to Theses, 2008. http://eprint.cc.andrews.edu/38/.
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Boyle, Rosemary. "Synthesis, structure and stereochemistry of metabolites from benzo-fused oxygen heterocycles." Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333789.
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Stephen, William Mark Linn. "The synthesis and kinetic resolution of a trans-fused bicyclic lactone." Thesis, University of Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435417.
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Iwata, Akira. "Development of Novel Methods for Synthesis of Fused Indole-Type Compounds." Kyoto University, 2018. http://hdl.handle.net/2433/232328.
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Noble, A. "Investigation into the use of 1,2-diamines in fused heterocycle synthesis." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1346443/.
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The introductory chapter of this thesis gives a brief outline of the literature concerning the importance of 1,2-diamines. This includes their biological significance, their successful application to synthetic chemistry, especially in asymmetric synthesis, and methods available for their preparation. One particular method, the nitro-Mannich reaction, is reviewed in more detail. The synthetic utility of the products of the nitro-Mannich reaction is demonstrated by their application to the synthesis of natural products and pharmaceutical agents. Improvements to the scope of the nitro-Mannich reaction through the development of conjugate addition nitro-Mannich reactions are also discussed, including a brief outline of the methods available for asymmetric conjugate additions to nitroalkenes. The introductory chapter closes with the importance of 1,2-diamine-containing fused heterocycles, especially in pharmacological compounds, and describes some of the methods available for their preparation. The results and discussion chapter gives a detailed account of the work that has been performed towards the development of an expedient synthesis of 1,2-diamine-containing fused heterocycles. The synthesis utilises a highly anti-selective reductive nitro-Mannich reaction to form structurally complex β-nitroamines in high yield. These are subsequently reduced to the corresponding 1,2-diamines, which undergo a palladium catalysed intramolecular N arylation to synthesise an array of fused heterocyclic compounds. This cyclisation reaction can be performed highly selectively to form both 2-aminomethylene indolines and 3-aminotetrahydroquinolines through the use of a trifluoroacetyl protecting group. Details of the optimisation studies for the nitro-Mannich, nitro reduction and intramolecular N-arylation reactions are given. Investigations into the further derivatisation of the heterocyclic products are also presented. Finally, investigations into the development of an alternative synthesis of tetrahydroquinolines utilising an intramolecular nitro-Mannich reaction are discussed. The conclusions drawn from the research have been summarised and future investigations to be carried out discussed, including the application of this new methodology to the synthesis of schizozygine. The experimental section presents detailed preparative methods and analytical data for all novel compounds. Finally, X-ray crystallographic data and a comprehensive list of references are provided in the appendices section.
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Robertson-Ralph, Michael J. "Photochemical synthesis and electrocyclic ring opening of cyclobutene-fused bicyclic systems." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.690756.
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This thesis has two main themes both with synthetic organic photochemistry at the centre of their research aims. The first deals with the synthesis of [2.0.n] cyclobutenes via the photo [2+2] cycloaddition of propargyl alcohol with an appropriate unsaturated anhydride followed by their thermal electrocyc1ic ring opening. According to molecular orbital theory this must occur via a conrotatory operation. However, this would lead to cis,trans dienes but only cis,cis dienes have, to date, been observed.
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Sandow, Lisa Rosemary. "The use of sulfonamide linkers, cyclopentenone templates and C-C bond coupling reactions for organic synthesis." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624288.
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Barabe, Francis. "Gold(I)-Catalyzed Synthesis of Polycyclic Frameworks Related to Terpenes: Selective Divergent Synthesis of Fused Carbocycles." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/29055.
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Gold catalysis has become an important tool to achieve highly chemoselective p-acid activation. Exceptional reactivity and selectivity are often encountered under mild reaction conditions. These properties have made gold(I) complexes suitable catalysts for tremendous applications in the total synthesis of natural products. The first chapter will highlight a number of total syntheses using gold catalysis as a key step.
The second chapter will cover our application of the gold(I)-catalyzed 6-endo-dig carbocyclization for the synthesis of bridgehead-substituted scaffolds and its use toward the synthesis of PPAP natural products. This research has opened our eyes to the utility of biphenylphosphine ligands, particularly JohnPhos, in gold(I)-catalysis.
The reactivity and selectivity exhibited by gold(I) complexes is modulated by the nature of the ancillary ligand. Recent research rationalizes the impact of these ligands on the divergent reactivity observed between cationic and carbenoid intermediates. Our desire to favor the 6-endo-dig pathway has led us toward the discovery of another example of the diagonal reactivity that NHC carbene and biphenylphosphine ligands can bring to gold(I)-catalysis. Chapter three will explain the development of a selective gold-catalyzed synthesis of fused carbocycles
.
Our selective divergent synthesis of fused carbocycles, combined with the Diels–Alder reaction, has brought new synthetic opportunities. Chapter four will describe our approach toward the synthesis of various polycyclic diterpene-related frameworks. Starting with a unique linear precursor, we have developed a new “one-pot” process for the synthesis of three different polycyclic compounds related to the terpenoid family. The facile modulation of the linear precursor and the use of different dienophiles during the Diels–Alder reaction could enable the synthesis of diverse polycyclic analogues based on three principal frameworks.
The gold(I)-catalyzed synthesis of fused carbocycles reached some limitations during our study. Regioselective control was found to be substantially more challenging, with terminal alkynes or alkynes bearing a sterically and electronically neutral methyl substituent. In chapter five, we will discuss how the complementarity of silver(I) catalysis to gold(I) catalysis enabled the selective divergent synthesis of three different fused carbocycles from a unique precursor. Moreover, copper(I) catalysis has given access to the 6-endo-dig pathway on terminal alkynes without the formation of a vinylidene intermediate.
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Hirano, Kimio. "Direct Synthesis of Fused Indoles by Gold-Catalyzed Intramolecular Alkyne Cycloisomerization Cascade." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/159419.
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Bengtsson, Christoffer. "Synthesis of substituted Ring-Fused 2-Pyridones and applications in chemical biology." Doctoral thesis, Umeå universitet, Kemiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-68709.
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Antibiotics have been extensively used to treat bacterial infections since Alexander Fleming’s discovery of penicillin 1928. Disease causing microbes that have become resistant to antibiotic drug therapy are an increasing public health problem. According to the world health organization (WHO) there are about 440 000 new cases of multidrug-resistant tuberculosis emerging annually, causing at least 150 000 deaths. Consequently there is an immense need to develop new types of compounds with new modes of action for the treatment of bacterial infections. Presented herein is a class of antibacterial ring-fused 2-pyridones, which exhibit inhibitory effects against both the pili assembly system in uropathogenic Escherichia coli (UPEC), named the chaperone usher pathway, as well as polymerization of the major curli subunit protein CsgA, into a functional amyloid fibre. A pilus is an organelle that is vital for the bacteria to adhere to and infect host cells, as well as establish biofilms. Inhibition of the chaperone usher pathway disables the pili assembly machinery, and consequently renders the bacteria avirulent. The focus of this work has been to develop synthetic strategies to more efficiently alter the substitution pattern of the aforementioned ring-fused 2-pyridones. In addition, asymmetric routes to enantiomerically enriched key compounds and routes to compounds containing BODIPY and coumarin fluorophores as tools to study bacterial virulence mechanisms have been developed. Several of the new compounds have successfully been evaluated as antibacterial agents. In parallel with this research, manipulations of the core structure to create new heterocycle based central fragments for applications in medicinal chemistry have also been performed.
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Shelton, Kerri. "NEW PHOTOVOLTAIC ACCEPTORS: SYNTHESIS AND CHARACTERIZATION OF FUNCTIONALIZED C-FUSED ANTHRADITHIOPHENE QUINONES." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_theses/92.
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Stable organic semiconductors are critical to produce inexpensive, efficient and flexible thin film organic solar cells. A current chemical focus is the synthesis of stable, electron-accepting materials to be utilized as an acceptor layer in photovoltaics.1 The Anthony group has shown that the functionalization of pentacene with suitable electron withdrawing groups provides a catalog of suitable acceptors for this purpose.2 These pentacenes can be further modified to pack in a unique 1-dimensional "sandwich herringbone" crystal packing, leading to improved device current.3 To improve the stability of acene acceptors, we have taken two hetero-atom themed approaches. First, we have studied the acenequinone as an electron-accepting chromophore.4 Further, we replaced the terminal aromatic rings with heterocycles, such as furan or thiophene. In order to enhance the crystal engineering versatility of the chromophore, we utilize c-fused heterocycles (rather than the more commonly used b-fused cycles seen in e.g. anthradithiophenes). The c-fused acenequinones can be tetra-functionalized with silylethynyl groups to influence crystal packing and increase solubility.5 The silylethyne groups are known to increase the photostability and lower the energy gap (Eg) of pentacenes.5 The functionalization of the silylethyne groups also aids in lowering the lowest unoccupied orbital (LUMO) of acene structures.5
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PAGANO, ANGELA. "Benzo-fused nitroheterocycles via benzannulation with nitro-1,3-butadienes: synthesis and application." Doctoral thesis, Università degli studi di Genova, 2020. http://hdl.handle.net/11567/999570.
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Nitroindoles, despite their scanty occurrence in nature, are attractive reactive intermediates in organic synthesis thanks to the coupling of the properties of the nitro group and of the indole moiety.[1] While nitration of the pyrrole nucleus can be easily achieved, nitration on the benzene ring represents a more challenging target. Ex-novo construction of the pyrrole onto a functionalized benzene derivative is, by far, the synthetic strategy most frequently exploited to access indole nitrated on the benzene ring. Herein, we expand the synthetic access to such nitroindoles reporting an original protocol based on the ex-novo construction of the benzene ring onto pyrrole employing mono- or dinitro-1,3-butadienes as powerful C4 benzannulating agents. This appealing, metal-free process characterized by high atom economy and mild reaction conditions allows to synthesize nitroindoles characterized by patterns of substitution not easy to be obtained otherwise.[2] Such unusual substitution patterns have demonstrated to be promising for further elaborations, i.e. the application of the classic Cadogan reaction conditions in order to access pyrrolocarbazoles with a rarely reported ring fusion.[3]
A very interesting side project regarded the synthesis of a series of atropisomeric naphthyl nitroindoles with two stereogenic axes originated from steric hindrances forcing the naphthyl groups out of the indole plane; the asymmetry of the indole “spacer” makes both the syn and anti diastereoisomers entail an atropisomeric pair. A stereodynamic analysis of such new atropisomeric nitroindoles has been done resolving atropisomers by chiral HPLC and determining their absolute configuration and the rotational barriers of the indole–naphthyl axes.[4]
This work, within an Erasmus+ project, demonstrates also the photochemical activity of electron donor-acceptor (EDA) complexes providing a way to generate radicals under mild conditions. This strategy has recently found application in chemical synthesis. Reported methods classically relied on the formation of intermolecular EDA complexes. Herein, we further expand the synthetic utility of this strategy demonstrating that indole-tethered ynones form an intramolecular electron donor-acceptor complex that can undergo visible-light-induced charge transfer to promote thiyl radical generation from thiols.[5] This initiates a novel radical chain sequence, based on dearomatizing spirocyclization with concomitant C–S bond formation. Sulfur-containing spirocycles are formed in high yields using this simple and mild synthetic protocol, in which neither transition metal catalysts nor photocatalysts are required. The proposed mechanism is supported by various mechanistic studies, and the unusual radical initiation mode represents only the second report of the use of an intramolecular electron donor-acceptor complex in synthesis.
[1] G. W. Gribble, in Prog. Heterocycl. Chem., Vol. 31, Elsevier, 2020, pp. 83-117.
[2] A. Pagano, M. Mancinelli, L. Bianchi, G. Giorgi, M. Maccagno, G. Petrillo, C. Tavani, Tetrahedron 2019, 75, 4506-4515.
[3] A. Benzi, L. Bianchi, M. Maccagno, A. Pagano, G. Petrillo, C. Tavani, Molecules 2019, 24, 3802.
[4] A. Pagano, E. Marotta, A. Mazzanti, G. Petrillo, C. Tavani, M. Mancinelli, Synlett 2018, 29, 2161-2166.
[5] H. E. Ho, A. Pagano, J. A. Rossi-Ashton, J. R. Donald, R. G. Epton, M. J. James, P. O'Brien, R. J. K. Taylor, W. P. Unsworth., Chem. Sci. 2020, DOI: 10.1039/c9sc05311e.
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Lam, Tsang Sing. "Synthesis and characterization of novel polymers : copolymers of Poly(phenyl vinyl sulfoxide) and Poly(amide sulfonamide)s." HKBU Institutional Repository, 1998. http://repository.hkbu.edu.hk/etd_ra/166.
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Hristeva, Stanimira [Verfasser]. "Development of new asymmetric organocatalytic domino reactions for the synthesis of (benzo-fused) five- and benzo-fused six-membered cyclic compounds / Stanimira Hristeva." München : Verlag Dr. Hut, 2016. http://d-nb.info/1094117803/34.
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Connolly, Terrence Joseph. "Fused bicyclic ortho-quinodimethanes and studies directed towards the synthesis of lysergic acid." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/10398.
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Chapters 3-6 outline attempts to generate a tri-fused sulfone and sultine suitable as an orthoquinodimethane precursor that could be used in a novel synthesis of lysergic acid. Several penultimate intermediates were prepared and characterized, but in no cases were the final steps successful. Attempted cyclization of 4-hydroxymethyl-3-thiomethyl-2-oxindole under basic conditions did not afford the desired tricycle and resulted in complicated reaction mixtures. Activation under acidic conditions (HI) resulted in dethiomethylation of the oxindole. This reaction led to the development of a mild, non-reductive method for the desulfenylation of 3-thioalkyl-2-oxindoles. Attempted cyclization of 3-thiobenzyl-4-hydroxymethylindole-S-oxide with NCS and SO$\sb2\rm Cl\sb2$ did not result in the formation of a tricyclic sultine. All the difficulties were believed to be due to the electron donating ability of the nitrogen, and aromatic ring system. A mechanism to account for the formation of a bicyclic chloro-sulfone rather than a tricyclic sultine is proposed. Factors influencing the metal hydride mediated reduction of pendant ester groups of 3-thiomethyl-2-oxindoles were probed by preparing a number of oxindole derivatives. It was found that if the oxindoles have a proton $\alpha$ to the oxindole carbonyl, then reduction of the pendant ester occurs first. If a proton is available at C3, then deprotonation occurs. If this center is ortho or para to the benzoate, then initial reduction is difficult, and over-reduction is common. For 1,3-dimethyl-3-thiomethyl-2-oxindoles, a different pathway is followed. Initial reduction of the oxindole carbonyl seems to occur first in this case. The intermediate hemi-aminal which results from the first hybride addition to the carbonyl may follow a number of pathways. An unusual rearrangement of the thiomethyl group from the 3 to 2 position was also observed. Mechanisms to explain these transformations are proposed. Finally, bicyclic ortho-quinodimethanes were prepared via two routes. New routes to a series of bicyclic carboxaldehydes followed by photo-enolization led to bicyclic ortho-quinodimethanes which were trapped with a series of dienophiles. An ionic route was also developed that led to the successful preparation of a 6-6-6 and a 6-6-7 tricyclicsulfone. Chelotropic expulsion of SO$\sb2$ led to ortho-quinodimethanes. Finally, the opportunity of explore the solid state mobility of N-methoxy-N-methyl-1,2,3,4-tetrahydronapthylcarboxamide presented itself. This compound was found to exhibit considerable mobility in the solid state. A cyclohexene-type inversion was found to take place with an apparent activation energy of 12.3 kJ/mol. An analogue which was di-deuterated at the 3 position was also prepared, and broad line $\sp2$H-NMR used to study its mobility. The corresponding acid was also found to be mobile, but with only limited mobility at higher temperatures. Although the dipolar dephased spectrum of the acid suggested that it was quite rigid, examination of the change in the line shape of the deuterated analogue at higher temperatures suggests that there is some, albeit limited, mobility. A single crystal X-ray diffraction study also supports the mobility of the amide. The crystal packing of the unit cell is believed to be responsible for this mobility. (Abstract shortened by UMI.)
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Wilkins, Derek. "Dicobaltoctacarbonyl species in organic synthesis : a novel route into tricyclic fused ring systems." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/55869/.
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This thesis describes the modern uses of cobalt carbonyl complexes in organic synthesis, by focusing primarily on the Pauson-Khand Reaction (PKR). This is where an alkyne, alkene and a dicobalt complex react in a (2+2+1) cycloaddition producing an cyclopentenone adduct. The cyclopentadienone products of the PKR were used in the synthesis of hetero fused tricyclic ring systems using a diastereoselective and regioselective chemical synthesis via the addition of soft organometallic nucleophiles: The nucleophilic addition of such species allowed a spontaneous cyclocondensation that gave fused ring systems with known biological activity prevalent in a wide range of natural products. This unique synthesis was then applied to non-hetero fused tricyclic ring systems affording a triquinane skeleton analogue which possess significant levels of biological activity. These syntheses were achieved by way of a three-step sequence after an initial PKR. A 1,4-Michael addition was followed by a 1,5-cyclisation and catalytic oxidation of an olefin resulting in the target tricyclic compound. Secondly, an investigation was performed into the regioselectivity of the PKR, using di-substituted alkynes with a high degree of conjugation, which were prepared by transition-metal catalysed cross couplings reactions. The isolation of the corresponding dicobalt alkyne complexes, and their gjto-tricyclodecadienone products were used to assist in elucidating the mechanism by which the PKR proceeds. The final Chapter describes the uses and mechanism, by which dinorbornadienedicobalttetracarbonyl (DDTC) was formed as a side product of the PKR. This side product was then used to promote the PKR. Surprisingly, only alkynes with electronegative oxygen atoms worked and diastereoselective control for the synthesis of cyclopentadienones was maintained at similar levels observed within the PKR with dicobaltoctacarbonyl.
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Claridge, Stephen. "Applications of cobalt stabilised carbonium ions to the synthesis of fused ring carbocycles." Thesis, Kingston University, 1996. http://eprints.kingston.ac.uk/20593/.
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This programme of work has been aimed at developing novel annulation reactions in order to furnish a variety of carbocyclic and heterocyclic ring systems: In all of the examples investigated the key cyclisation step was achieved using a Nicholas reaction, that is, the reaction of a dicobalt hexacarbonyl stabilised propargylic carbonium ion with an intramolecular nucleophile. After an initial review of both cyclisation reactions and the chemistry of organocobalt clusters, the results of these investigations are detailed. In the initial investigations a range of 1,2-disubstituted cycloalkanes were synthesised that contained a dicobalt hexacarbonyl complexed propargyl ether at the a-carbon atom and a pendant silyl enol ether at the ß-carbon atom. These molecules were successfully cyclised, using boron trifluoride diethyl etherate followed by decomplexation of the dicobalt cluster, to afford a bicyclo[4:3:0]nonane, two bicyclo[3:3:0]octanes and a bicyclo[5:3:0]decane. The relative stereochemistry at the fused ring junction for all these molecules was determined on the basis of their corresponding =c NMR spectra. An analogous reaction was successfully achieved between a dicobalt hexacarbonyl complexed prop argyl ether and a terminal alkene, using titanium (IV) chloride, to afford a cis fused bicyclo[3:3:0]octane into which a chlorine atom had been incorporated. A subsequent investigation led to the development of a novel benzopyran synthesis. In this approach two benzopyran derivatives were produced from the one key cyclisation precursor. It was observed that they not only contained different functionalities but that the relative stereochemistry at the newly formed carbon-carbon bonds was different. A benzopyran, that possessed the isopropenyl group, exhibited a trans stereochemistry, whereas the stereochemistry for a second fluorinated derivative appeared, from the magnitude of the coupling constant (6 Hz), to exhibit a cis stereochemistry. The concluding investigation focused upon the intramolecular cyclisation of a precursor derived from S-C - )-citronellal. Both a silyl enol ether derivative andan allyl silane derivative were successfully cyclised, using the Nicholas reaction, to affordtrisubstituted cycloalkanes in low but unoptimised yields. An additional investigation using a dicobalt hexacarbonyl complexed derivative possessing a pendant trisubstituted alkene underwent a novel cyclisation reaction to furnish, upon decomplexation, two trisubstituted cycloalkane derivatives. For one of the cycloalkanes produced, the relative stereochemistry of the ring substituents at the newly formed carbon-carbon bond was found to be trans.
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Hoffman, William Christopher. "Synthesis of fused carbocycles from benzoic acids via radical and anionic annulation procedures /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487331541711284.
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Willumstad, Thomas P. (Thomas Paul). "Synthesis of highly substituted benzo-fused nitrogen heterocycles via tandem benzannulation/cyclization strategies." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/84379.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2013.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references.<br>Benzannulations employing ynamides and vinylketenes (generated in situ from [alpha]-diazo ketones) were investigated. Irradiation of the diazo ketones using a batch or continuous-flow reactor leads to the formation of vinylketenes via a photo-Wolff rearrangement. The vinylketenes then react with ynamides via a pericyclic cascade process to produce highly substituted aniline derivatives. Using this vinylketene-based benzannulation, tandem strategies for the synthesis of highly substituted benzo-fused nitrogen heterocycles were investigated. A tandem benzannulation-iodocyclization method for the synthesis of polysubstituted quinolines was established. In addition, a tandem strategy for the synthesis of carbazoles was developed and applied in the total synthesis of the carbazole alkaloid carazostatin as well as formal syntheses of the alkaloids carbazoquinocin C and antiostatin A₄.<br>by Thomas P. Willumstad.<br>Ph.D.