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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Thermal rearrangements in the indene system

Aspelin, Gary Bertil, January 1966 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1966. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Pyrolytic Study of 1-Azidoindene and 3-(4-Methoxystyryl)thiophene

Hsueh, Yu-tan 30 August 2005 (has links)
Flash vacuum pyrolysis (FVP) of 1-azidoindene, which via a nitrene intermediate, gave some products of rearrangement¡Gquinoline¡Bisoquinoline and 1-methylene-1H-isoindole¡CUnder pyrolytic conditions, 3-(4-methoxystyryl)thiophene could get a radical intermediate and gave 3-(4-hydroxystyryl)thiophene, or it gave contractive tricyclic compounds which having signals on spectrum but inseparable, like as indene structures.
3

Photo-additions of lndenes and Naphthalene with Acrylonitrile

Huang, Chaog-wei 05 1900 (has links)
The products and mechanisms of some photo-reactions of indenes and naphthalene with acrylonitrile have been studied. Indene reacts with acrylonitrile with the hydrocarbon absorbs light, or when a triplet sensitizer is absorbing. Photolysis under the former condition yields 2-(1-indenyl)- and 2-(3-indenyl)propionitrile, and 6-cyano-2,3-benzobicyclo[3,2,0]hep-2-ene. Base-catalyzed isomerizations of the substituted indenes are reported. On sensitization, cis- and trans-isomers of 7-cyano-2,3-benzobicyclo[3,2,0]hep-2-ene are formed; the known indene dimer is a minor product. Adducts 1,1-dimethyl- and 1,1-diphenylidene with acrylonitrile are also described. Naphthalene adds to acrylonitrile on photolysis to afford trans-8-cyano-2,3-benzobicyclo[4.2.0] octa-2,4-diene and 1- and 2-naphthyl-2-propionitriles. Sensitization gives no detectable products. Studies on fluorescence quenching, solvent effect and deuterium-labelling indicates that exciplexes are formed between acrylonitrile and the excited hydrocarbons. Inter- or intra-molecular protonation of the exciplexes with subsequent reaction of the carbonium ion formed, is suggested to produce indenes or naphthalenes. Possible mechanisms for the formation of other products are proposed. / Thesis / Doctor of Philosophy (PhD)
4

Pyrolytic study of para-methoxystyrylarenes, 2-azidocyclohexanone and 6-arylfulvenes

Chu, Li-Tse 22 July 2005 (has links)
1. FVP of para-methoxystyrylarenes (5a-c) all gave the corresponding phenol products 21a-c. FVP of 5a and 5c also gave tricyclic products 22 and 23, respectively, which all included indene structure. But FVP of 5b gave naphthalene by ring opening of the furan. 2. FVP of 2-azidocyclohexanone (70) gave four products 83-86, and product 84 was a new compound. We provided a method to synthesize a new tricyclic product by one step. 3. Pyrolytic study of five 6-arylfulvenes (78-82). The products from FVP of 78-82 and mechanisms to account for their products will be discussed. FVP of compounds 79 and 80 gave naphthalene (96) and indene (97), respectively, by elimination of either a S or a CO molecule.
5

Poli(indeno) fosfonado : síntese, propriedades e uso como eletrólito em membranas a base de PBI

Freitas, Mauricio Azevedo de January 2018 (has links)
Neste trabalho, um polímero eletrólito derivado do poli(indeno) (PInd) foi desenvolvido como componente de membranas poliméricas a base de polibenzimidazol (PBI) para célula a combustível de média temperatura. Foi investigado o método de síntese, envolvendo a reação de fosfonação pelo método de Friedel-Crafts assistido por catalisador ácido de Lewis AlCl3. O polímero poli(indeno) fosfonado (PPInd) foi comparado com seu análogo sulfonado, o poli(indeno) sulfonado (SPInd), e usados nas blendas com 5, 7,5 e 10% em peso com o PBI. Os polímeros precursores foram caracterizados por espectroscopia de infravermelho, espectroscopia de ressonância magnética nuclear, espectroscopia de energia dispersiva, espectrometria de espalhamento Rutherford, análise termogravimétrica acoplada com espectrometria de massas e calorimetria exploratória diferencial. As blendas PPInd/PBI e SPInd/PBI foram caracterizadas por análise termogravimétrica, grau de dopagem e espectroscopia de impedância eletroquímica. A modificação realizada pelo método de Friedel-Crafts permitiu a obtenção do poli(indeno) fosfonado parcialmente solúvel em solventes orgânicos e água, com grau de modificação de 81%. Houve convergência dos teores de modificação encontrados pelas análises termogravimétrica, espectrometria de espalhamento Rutherford e espectroscopia de energia dispersiva. O polímero PPInd apresentou estabilidade química na temperatura de operação da célula a combustível de média temperatura, passando por processos de degradação típicos de sua estrutura aromática fosfonada. A degradação dos polímeros PInd, PPInd e SPInd ocorreu majoritariamente com cisão de unidades monoméricas de indeno não funcionalizado. A inserção dos polímeros modificados PPInd e SPInd no PBI resultou no aumento da condutividade iônica, tendo a blenda com 10% de PPInd apresentado o maior valor de condutividade protônica (0,015 S.cm-1), a 25 oC. O uso do poli(indeno) modificado com grupos ácido fosfônico visa aumentar a gama de eletrólitos para células a combustível de média temperatura. / In this work a polymer electrolyte derivated from the poly(indene) (PInd) was developed to be used as polymer electrolyte membrane in medium-temperature fuel cells. The modification method, based on the AlCl3 assisted Friedel-Crafts reaction, was investigated as fosfonation strategy. The phosphonated poly(indene) was compared to its similar sulphonated poly(indene) and they were used in blends of 5, 7.5 and 10wt% in polybenzimidazole (PBI). Pristine polymers were characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, energy dispersive spectroscopy, Rutherford backscattering spectrometry, thermogravimetric analysis coupled with mass spectrometry and differential scanning calometry. The PPInd/PBI and SPInd/PBI blends were characterized by thermogravimetric analysis, doping level and electrochemical impedance spectroscopy. The modification by Friedel-Crafts reaction produced phophonated poly(indene) with degree of phosphonation of 81%, partially soluble in organic solvent and water. It was found convergence on the results for degree of phosphonation calculated by thermogravimetric analysis, Rutherford backscattering spectrometry and energy dispersive spectroscopy. PPInd presented chemical and thermal stabilities within the fuel cell operating temperature, passing by typical degradation processes of macromolecules made of phosphonated aromatic structures. The degradation of PPInd and SPInd occurred mainly by cleavage of monomeric units of non-funcionalized indene. Addition of modified polymers PPInd and SPInd resulted in increase of PBI’s ionic conductivity. 10PPInd/PBI blend presented the highest ionic conductivity (0.015 S.cm-1) at 25 oC. The use of phosphonated poly(indene) on PBI membranes enlarges the variety of available polymer electrolyte membranes for medium-temperature fuel cells.
6

Development and Investigation of Electrocyclization Reactions Leading Towards Indene and Thiatriazole Formation and their Functionalization

Rosocha, Yaroslav Gregory S. 19 January 2012 (has links)
No description available.
7

Poli(indeno) fosfonado : síntese, propriedades e uso como eletrólito em membranas a base de PBI

Freitas, Mauricio Azevedo de January 2018 (has links)
Neste trabalho, um polímero eletrólito derivado do poli(indeno) (PInd) foi desenvolvido como componente de membranas poliméricas a base de polibenzimidazol (PBI) para célula a combustível de média temperatura. Foi investigado o método de síntese, envolvendo a reação de fosfonação pelo método de Friedel-Crafts assistido por catalisador ácido de Lewis AlCl3. O polímero poli(indeno) fosfonado (PPInd) foi comparado com seu análogo sulfonado, o poli(indeno) sulfonado (SPInd), e usados nas blendas com 5, 7,5 e 10% em peso com o PBI. Os polímeros precursores foram caracterizados por espectroscopia de infravermelho, espectroscopia de ressonância magnética nuclear, espectroscopia de energia dispersiva, espectrometria de espalhamento Rutherford, análise termogravimétrica acoplada com espectrometria de massas e calorimetria exploratória diferencial. As blendas PPInd/PBI e SPInd/PBI foram caracterizadas por análise termogravimétrica, grau de dopagem e espectroscopia de impedância eletroquímica. A modificação realizada pelo método de Friedel-Crafts permitiu a obtenção do poli(indeno) fosfonado parcialmente solúvel em solventes orgânicos e água, com grau de modificação de 81%. Houve convergência dos teores de modificação encontrados pelas análises termogravimétrica, espectrometria de espalhamento Rutherford e espectroscopia de energia dispersiva. O polímero PPInd apresentou estabilidade química na temperatura de operação da célula a combustível de média temperatura, passando por processos de degradação típicos de sua estrutura aromática fosfonada. A degradação dos polímeros PInd, PPInd e SPInd ocorreu majoritariamente com cisão de unidades monoméricas de indeno não funcionalizado. A inserção dos polímeros modificados PPInd e SPInd no PBI resultou no aumento da condutividade iônica, tendo a blenda com 10% de PPInd apresentado o maior valor de condutividade protônica (0,015 S.cm-1), a 25 oC. O uso do poli(indeno) modificado com grupos ácido fosfônico visa aumentar a gama de eletrólitos para células a combustível de média temperatura. / In this work a polymer electrolyte derivated from the poly(indene) (PInd) was developed to be used as polymer electrolyte membrane in medium-temperature fuel cells. The modification method, based on the AlCl3 assisted Friedel-Crafts reaction, was investigated as fosfonation strategy. The phosphonated poly(indene) was compared to its similar sulphonated poly(indene) and they were used in blends of 5, 7.5 and 10wt% in polybenzimidazole (PBI). Pristine polymers were characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, energy dispersive spectroscopy, Rutherford backscattering spectrometry, thermogravimetric analysis coupled with mass spectrometry and differential scanning calometry. The PPInd/PBI and SPInd/PBI blends were characterized by thermogravimetric analysis, doping level and electrochemical impedance spectroscopy. The modification by Friedel-Crafts reaction produced phophonated poly(indene) with degree of phosphonation of 81%, partially soluble in organic solvent and water. It was found convergence on the results for degree of phosphonation calculated by thermogravimetric analysis, Rutherford backscattering spectrometry and energy dispersive spectroscopy. PPInd presented chemical and thermal stabilities within the fuel cell operating temperature, passing by typical degradation processes of macromolecules made of phosphonated aromatic structures. The degradation of PPInd and SPInd occurred mainly by cleavage of monomeric units of non-funcionalized indene. Addition of modified polymers PPInd and SPInd resulted in increase of PBI’s ionic conductivity. 10PPInd/PBI blend presented the highest ionic conductivity (0.015 S.cm-1) at 25 oC. The use of phosphonated poly(indene) on PBI membranes enlarges the variety of available polymer electrolyte membranes for medium-temperature fuel cells.
8

Explorations of Cascading Michael Additions

Young, Douglas M. 09 1900 (has links)
xx, 214 p. : ill. (some col.) / Intramolecular cascading Michael additions have the ability to transform simple, symmetric substrates into densely functionalized compounds containing new ring structures and chiral centers. The Rauhut-Currier (RC) reaction, also known as the vinylogous Morita-Baylis-Hillman reaction, utilizes this type of reactivity by cyclizing tethered, activated alkenes using phosphine or thiolate catalysis. This dissertation describes the expansion of the scope of the RC reaction, the introduction and importance of co-catalysts to cascading Michael additions, the development of the first amine-catalyzed RC reaction, and the transformation of cyclization products into fused, polycyclic aromatic compounds. Chapter I reviews the development and applications of the Rauhut-Currier reaction. Chapter II describes the regioselective synthesis of di-substituted indenes and introduces phenol as a rate- and selectivity-enhancing co-catalyst. Although tertiary amine nucleophiles were found to be inferior to phosphines as cyclization catalysts, chapter III discusses the ability of unhindered primary and secondary amines to undergo a diastereoselective, cascading aza-Michael-Michael addition to yield a wide variety of amino-indanes in the presence of an acid catalyst. Recognizing the importance of protic environments and small nucleophiles, the development of the first amine-catalyzed intramolecular RC is introduced in chapter IV. Chapter V describes the conversion of methyl ketone-substituted indenes to fluorene derivatives via an intramolecular aldol reaction. Chapter VI describes the serendipitous discovery and synthesis of indenopyrylium salts. Chapter VII details the novel production of indenopyridines from di-substituted indenes. Lastly, chapter VIII provides a summary and suggests future directions for this research. This dissertation includes previously published and unpublished co-authored material. / Committee in charge: Shih-Yuan Liu, Chairperson; Kenneth Doxsee, Advisor; David Tyler, Member; Michael Haley, Member; A. Dana Johnston, Outside Member
9

Poli(indeno) fosfonado : síntese, propriedades e uso como eletrólito em membranas a base de PBI

Freitas, Mauricio Azevedo de January 2018 (has links)
Neste trabalho, um polímero eletrólito derivado do poli(indeno) (PInd) foi desenvolvido como componente de membranas poliméricas a base de polibenzimidazol (PBI) para célula a combustível de média temperatura. Foi investigado o método de síntese, envolvendo a reação de fosfonação pelo método de Friedel-Crafts assistido por catalisador ácido de Lewis AlCl3. O polímero poli(indeno) fosfonado (PPInd) foi comparado com seu análogo sulfonado, o poli(indeno) sulfonado (SPInd), e usados nas blendas com 5, 7,5 e 10% em peso com o PBI. Os polímeros precursores foram caracterizados por espectroscopia de infravermelho, espectroscopia de ressonância magnética nuclear, espectroscopia de energia dispersiva, espectrometria de espalhamento Rutherford, análise termogravimétrica acoplada com espectrometria de massas e calorimetria exploratória diferencial. As blendas PPInd/PBI e SPInd/PBI foram caracterizadas por análise termogravimétrica, grau de dopagem e espectroscopia de impedância eletroquímica. A modificação realizada pelo método de Friedel-Crafts permitiu a obtenção do poli(indeno) fosfonado parcialmente solúvel em solventes orgânicos e água, com grau de modificação de 81%. Houve convergência dos teores de modificação encontrados pelas análises termogravimétrica, espectrometria de espalhamento Rutherford e espectroscopia de energia dispersiva. O polímero PPInd apresentou estabilidade química na temperatura de operação da célula a combustível de média temperatura, passando por processos de degradação típicos de sua estrutura aromática fosfonada. A degradação dos polímeros PInd, PPInd e SPInd ocorreu majoritariamente com cisão de unidades monoméricas de indeno não funcionalizado. A inserção dos polímeros modificados PPInd e SPInd no PBI resultou no aumento da condutividade iônica, tendo a blenda com 10% de PPInd apresentado o maior valor de condutividade protônica (0,015 S.cm-1), a 25 oC. O uso do poli(indeno) modificado com grupos ácido fosfônico visa aumentar a gama de eletrólitos para células a combustível de média temperatura. / In this work a polymer electrolyte derivated from the poly(indene) (PInd) was developed to be used as polymer electrolyte membrane in medium-temperature fuel cells. The modification method, based on the AlCl3 assisted Friedel-Crafts reaction, was investigated as fosfonation strategy. The phosphonated poly(indene) was compared to its similar sulphonated poly(indene) and they were used in blends of 5, 7.5 and 10wt% in polybenzimidazole (PBI). Pristine polymers were characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, energy dispersive spectroscopy, Rutherford backscattering spectrometry, thermogravimetric analysis coupled with mass spectrometry and differential scanning calometry. The PPInd/PBI and SPInd/PBI blends were characterized by thermogravimetric analysis, doping level and electrochemical impedance spectroscopy. The modification by Friedel-Crafts reaction produced phophonated poly(indene) with degree of phosphonation of 81%, partially soluble in organic solvent and water. It was found convergence on the results for degree of phosphonation calculated by thermogravimetric analysis, Rutherford backscattering spectrometry and energy dispersive spectroscopy. PPInd presented chemical and thermal stabilities within the fuel cell operating temperature, passing by typical degradation processes of macromolecules made of phosphonated aromatic structures. The degradation of PPInd and SPInd occurred mainly by cleavage of monomeric units of non-funcionalized indene. Addition of modified polymers PPInd and SPInd resulted in increase of PBI’s ionic conductivity. 10PPInd/PBI blend presented the highest ionic conductivity (0.015 S.cm-1) at 25 oC. The use of phosphonated poly(indene) on PBI membranes enlarges the variety of available polymer electrolyte membranes for medium-temperature fuel cells.
10

Functionalization Of Saturated Hydrocarbons: High Temperature Bromination

Gunbas, Duygu Deniz 01 June 2006 (has links) (PDF)
ABSTRACT FUNCTIONALIZATION OF SATURATED HYDROCARBONS: HIGH TEMPERATURE BROMINATION G&uuml / nbaS, Duygu Deniz M.S., Department of Chemistry Supervisor: Prof. Dr. Metin Balci June 2006, 174 pages Although saturated hydrocarbons are readily available and extremely cheap starting materials, they can not be used in synthetic chemistry without prior activation. Efficient functionalization of alkanes leading to the production of useful organic chemicals in an industrial scale is of considerable interest for the chemical and pharmaceutical industries and remains a long-term challenge for chemists. In this respect, halogenations of hydrocarbons which leads to a variety of useful synthetic intermediates is an open avenue which deserves special attention. It is also noteworthy to mention that efficient methods for selective functionalization of saturated bicyclic hydrocarbons still remains elusive, albeit a number of methods employing various reagents have been developed for the C&amp / #8211 / H bond activation of open chain and monocyclic alkanes. Herein, we will investigate the high temperature bromination reactions as a method for functionalization of saturated bicyclic hydrocarbons such as octahydropentalene (1), octahydro-1H-indene (2) and 1a,2,7,7a-tetrahydro-1H-cyclopropa[b]naphthalene (3). The scope and the limitations of the reaction will reveal the regio-and stereoselectivity. Furthermore, formation mechanism of the products will be discussed and the chemistry of these compounds will be extended for further functionalization

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