Dissertations / Theses on the topic 'Heek'
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Heek, Peter [Verfasser]. "Modellbildung und numerische Analysen zur Ermüdung von Stahlfaserbeton / Peter Heek." Aachen : Shaker, 2018. http://d-nb.info/1159836922/34.
Full textHeek, Timm [Verfasser]. "Synthesis and Application of Water-Soluble Dendronized Rylene Dyes / Timm Heek." Berlin : Freie Universität Berlin, 2013. http://d-nb.info/1041874367/34.
Full textKrebbers-van, Heek Stephanie [Verfasser]. "Die mitunternehmerische Besteuerung der Komplementäre der Kommanditgesellschaft auf Aktien / Stephanie Krebbers-van Heek." Frankfurt : Peter Lang GmbH, Internationaler Verlag der Wissenschaften, 2016. http://d-nb.info/1090773811/34.
Full textHeek, Peter [Verfasser], Peter [Gutachter] Mark, and Ludger [Gutachter] Lohaus. "Modellbildung und numerische Analysen zur Ermüdung von Stahlfaserbeton / Peter Heek ; Gutachter: Peter Mark, Ludger Lohaus ; Fakultät für Bau- und Umweltingenieurwissenschaften." Bochum : Ruhr-Universität Bochum, 2018. http://d-nb.info/1154308146/34.
Full textNguyen, Huyen. "Heel Me." Thesis, Halmstad University, School of Business and Engineering (SET), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-957.
Full textHigh heels – a fashion that has not gone out of style after hundreds of years. Despite their esthetic advantages, high heels become uncomfortable and harmful after repetitive and long term use. With this as a starting point, Huyen Nguyen – a student at the Innovation Engineering Program at the University of Halmstad – decided to make a final thesis project.
The project goal has been to combine the esthetic advantages of high heels and bring a comfortable solution to the equation. The result was a shoe with an adjustable heel, tentatively named Heel Me.
During the project the production of shoes has been examined, a dialog with the shoe company Vagabond has been established and contacts abroad that can aid in the production have been established. Those involved with this project see it not as the end of a thesis, but as the beginning of a product yet to be found on the market.
Coomans, Fons. "Over nationale grenzen heen." Maastricht : Maastricht : Universiteit Maastricht ; University Library, Maastricht University [Host], 2007. http://arno.unimaas.nl/show.cgi?fid=13135.
Full textDe, Araújo Ferreira Fernanda. "Unraveling the high heel." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/128977.
Full textCataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 13-15).
Health foe. Confidence booster. Female oppressor. No other shoe style has taken on as many roles as the high heel or had those roles as passionately debated. Throughout their long history in Western fashion, high heels have changed shape and had new ideas about femininity, performance and compliance heaped on them Warnings about the health dangers of chronic high heel use also have a long history, with medical professionals counselling against them for almost 300 years. Still high heels have remained a staple of womenswear, always returning after brief sojourns out of style. This thesis unpack s the high heel, first looking at the effects of high heel use on the body before turning to the history of the high heel and discussing the reasons why countless w omen have endured a shoe that is by design uncomfortable. Then we look at attempts to reengineer high heels so that they are more comfortable for wearers and discuss the future of high heels in the footwear landscape. The thesis concludes with a discussion of how attempting to fathom the long narrative of high heels can change your relationship with the object.
by Fernanda de Araújo Ferreira.
S.M. in Science Writing
S.M.inScienceWriting Massachusetts Institute of Technology, Department of Comparative Media Studies/Writing
Heer, Thomas [Verfasser]. "Controlling Development Processes / Thomas Heer." Aachen : Shaker, 2011. http://d-nb.info/1070150738/34.
Full textHandy, Markus. "Die Severer und das Heer." Berlin Verl. Antike, 2009. http://bvbm1.bib-bvb.de/webclient/DeliveryManager?pid=491300&customa̲tt2̲=simplev̲iewer.
Full textHandy, Markus. "Die Severer und das Heer." Berlin VA, Verl. Antike, 2006. http://d-nb.info/993295126/04.
Full textMorales, Alfredo Louis. "Detachable high heel shoe construction." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40448.
Full text"June 2007."
Includes bibliographical references (leaf 30).
The goal on this investigation was to develop a detachable high heel shoe construction that could enter the current high heel market. The impact of high heel shoes on women's fashion is enormous but there are associated issues of comfort and health with these shoes. This work aims to maintain the appealing aspects of a high heel shoe while adding a concealed mechanism to enable the heel to be easily removed to convert the shoe into a flat at the discretion of the user. The current solutions and products in the nearly 7 billion dollar a year women's shoe market are minimal. The prior arts of detachable heels fail to develop a simple comprehensive detachable high heel that can enter the market. A feasible and complete design that takes into account arch stiffness, heel removal, styling, and manufacturability is the goal of this work. This investigation deconstructed high heel shoes to learn and leverage the current high heel shoe infrastructure as a basis for adapting the shoe into a detachable high heel shoe construction. Three prototypes of the detachable high heel shoe were developed with a shoe assembly that consisted of a modified insole and a detachable heel that consisted of a dovetailed aluminum shank fastened to a high heel.
(cont.) The prototypes were able to display the ability for the detachable high heel to maintain high heel stability, styling that is consistent with the industry, ease of use, a flat shoe and other critical functional requirements identified in the work. The construction was consistent with the current industry high heel infrastructure. The development of the detachable high heel construction displays the feasibility of such a product in a market where none exist. The detachable high heel construction needs further refinement and optimization to complete a design that is ready to enter this exciting market.
by Alfredo Louis Morales.
S.B.
Wittke-Rüdiger, Petra. "Literarische Kartographien des kanadischen Nordens /." Würzburg : Königshausen & Neumann, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2608042&prov=M&dok_var=1&dok_ext=htm.
Full textSennewald, Roland. "Das Kursächsische Heer im Dreißjährigen Krieg." Universität Potsdam, 2005. http://opus.kobv.de/ubp/volltexte/2008/2063/.
Full textMcConville, Matthew. "New directions in the Heck reaction." Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.533986.
Full textSchell, Friedrich Alexander. "Feste Katalysatoren für die Heck-Reaktion." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11244193.
Full textBarbosa, Marcelo Consiglio. "Adolf Franz Heep: um arquiteto moderno." Universidade Presbiteriana Mackenzie, 2012. http://tede.mackenzie.br/jspui/handle/tede/2566.
Full textThe objective of this research is to analyze the architectural contributions of Franz Heep in the post-war context during the development of the emerging metropolis of São Paulo which was financed by coffee production capital and also in part by foreign capital along with the contribution of immigrant architects between the period of 1945 and 1960. The motivation for this thesis is not to create a mere biographical piece, but to understand his particular architectural language and the relationship of his architectural pieces and the city. It also finds motivation in trying to understand the question of cultural transposition in which several cultural principals originated in Germany in the 20´s and in France in the 30´s had to adjust to be introduced into the Brazilian cultural context. To understand this transposition, much research was done in order to be able to distance the focus from Heep and try to understand the architectural scenery in Brazil at the time he was in the country, paying special attention to the cultural, economic and political dialogues between the respective spokesmen of the metropolis and the architect. The research analyzes the origins of Heep´s formation, his professional choices and his first office in partnership with Jean Ginsberg in Paris during 30´s, the contribution of immigrant architects as vectors of modernity for the real estate market, and Heep´s work with Jacques Pilon and his office from 1948 to 1952, where many buildings in the center of São Paulo were developed and, by consequence, a mark of excellence was established during the prelude of the real estate market during 1952 to 1960.
O objetivo desta pesquisa é analisar a produção arquitetônica de Franz Heep, à luz do desenvolvimento da cidade de São Paulo no pós guerra, financiado pelo capital cafeeiro e em parte pelo capital estrangeiro e a contribuição dos arquitetos imigrantes, auxiliando na construção da metrópole emergente entre 1945 e 1960. A motivação desta tese não é somente escrever uma biografia intelectual, mas entender as diversas interlocuções na obra de Heep e sua relação com a cidade. É também entender a questão da transposição cultural, onde um conjunto de princípios culturais de seu ambiente de origem, a Alemanha da década de 1920 e a França da década de 1930, terão vários ajustes para seu entrosamento no ambiente cultural do Brasil, procurando a pesquisa por vezes distanciar-se do foco somente à obra de Franz Heep e tentar compreender o cenário arquitetônico da época de sua estada no Brasil e seus personagens, atenta às trocas de diálogos culturais, econômicos, políticos e sociais da metrópole com o arquiteto. Na pesquisa são analisadas as origens de sua formação, suas escolhas profissionais, seu primeiro escritório em sociedade com Jean Ginsberg, em Paris da década de 1930, a contribuição dos arquitetos imigrantes como vetores de modernidade para o mercado imobiliário, o trabalho de Heep com Jacques Pilon de 1948 a 1952 e seu próprio escritório, onde desenvolve vários prédios no centro de São Paulo e define uma marca de excelência no prelúdio do mercado imobiliário de 1952 a 1960.
Pollehn, Hannes [Verfasser], Martin [Akademischer Betreuer] Henk, Martin [Gutachter] Henk, Monika [Gutachter] Ludwig, and Deane [Gutachter] Yang. "Subspace concentration of geometric measures / Hannes Pollehn ; Gutachter: Martin Henk, Monika Ludwig, Deane Yang ; Betreuer: Martin Henk." Berlin : Technische Universität Berlin, 2019. http://d-nb.info/118242306X/34.
Full textMiles, Kelsey C. "Palladium-Catalyzed Carbocyclizations of Substituted Benzoic Acids and Tandem One-Pot Acyl Heck/Heck Coupling of Indanones." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1377003454.
Full textHeck, Kimberly Keough. "Patient\'s perception of the helpfulness of education materials for breast cancer." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/heck/HeckK0508.pdf.
Full textGrüber, Raymond. "Etude théorique de réactions de Heck intramoléculaires." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2014. http://tel.archives-ouvertes.fr/tel-01061148.
Full textSellarajah, Shane. "Chiral additives in the asymmetric Heck reaction." Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390653.
Full textMcDermott, Michael Cory. "Asymmetric Heck reaction : conformational effects and enantioselectivity." Thesis, University of East Anglia, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426670.
Full textSmith, Andrew. "The cationic Heck reaction : a computational study." Thesis, University of Warwick, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369388.
Full textScherrer, Philipp. "Das Parlament und sein Heer das Parlamentsbeteiligungsgesetz." Berlin Duncker & Humblot, 2008. http://d-nb.info/1000336271/04.
Full textVaz, Boniek Gontijo. "Perspectivas mecanisticas de reações organicas catalisadas por paladio : Heck, oxa-Heck e acoplamento de Buchwald-Hartwig por ESI-MS/MS." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248671.
Full textDissertação (mestrado)- Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: A espectrometria de Massas por eletronspray (ESI-MS) tornou-se um método prático para o estudo de mecanismos reacionais em solução. Neste trabalho importantes reações catalisadas por paládio: reação de Heck-Mizoroki, oxa-Heck e o acoplamento de Buchwald-Hartwig foram monitoradas por ESI-MS visando interceptar espécies que comprovam as atuais propostas mecanísticas ou que abram caminho para novas propostas para estas reações. O monitoramento das reações foi realizado no modo off-line, acompanhamento da reação em intervalos pré-definidos de tempo, no qual alíquotas das soluções reacionais foram retiradas e diluídas em solventes apropriados e injetados por infusão direta no QTOF. Importantes intermediários reacionais destas reações foram interceptados por ESI-MS e caracterizados por ESI-MS/MS, o que possibilitou confirmar as espécies catalíticas responsáveis pela formação da ligação carbono-carbono na reação de Heck-Mizoroki, os principais intermediários para proposta mecanística desta reação e as atuais propostas da reação oxa-Heck e do acoplamento de Buchwald-Hartwig. No caso da reação oxa-Heck, os paladaciclos interceptados são os primeiros indícios experimentais para atual proposta mecanística desta interessante transformação
Abstract: Eletronspray ionization mass spectrometry (ESI-MS) has become a practical tool to study reaction mechanisms in solution. In this work important reactions catalyzed by palladium: Heck-Mizoroki reaction, oxa-Heck reaction and Buchwald-Hartwig coupling were monitored by ESI-MS to intercept transient intermediates that show the current mechanistic proposals or to open the way for new proposals for these reactions. These reaction was monitored in offline mode, whereas aliquots of the reaction solutions were withdrawn and diluted in appropriate solvents and injected by direct infusion at the Q-TOF in pre-defined intervals of time. Important intermediates from these reactions were intercepted by ESI-MS and characterized by its tandem version ESI-MS/MS, which allowed confirming the catalytic species responsible for the formation of carbon-carbon bond in the Heck-Mizoroki reaction, the main intermediaries mechanistic proposal from this reaction and the current proposals of oxa-Heck reaction and the Buchwald-Hartwig coupling. In oxa-Heck reaction, the intercepted palladacycles are the first experimental evidence for this current mechanistic proposal for this interesting transformation
Mestrado
Quimica Organica
Mestre em Química
Costenaro, Edson Roberto. "Utilização de enecarbamatos endociclicos na sintese de azanucleosideos." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249883.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: Nos últimos anos existe um grande interesse na obtenção de nucleosídeos e derivados estruturalmente relacionados em virtude do amplo espectro de atividades biológicas apresentadas por essa classe de compostos. Diversos tipos de análogos apresentando as mais diversas alterações estruturais têm sido relatados, entre os quais os azanucleosídeos, onde o átomo de oxigênio da porção glicosídica é substituído por um átomo de nitrogênio. Na primeira parte deste trabalho vários enecarbamatos endocíclicos quirais de cinco membros, enantiomericamente puros (CG-quiral), foram obtidos em uma seqüência de sete etapas a partir do ácido L-glutâmico e utilizados na síntese de azanucleosídeos. Na segunda parte deste trabalho utilizou-se a adição eletrofílica de brometo de fenilselenenila à enecarbamatos endocíclicos como etapa chave na obtenção de uma série de N-azanucleosídeos inéditos (estruturalmente relacionados às drogas atualmente utilizadas no coquetel anti-HIV). Na última parte deste trabalho, durante um estudo que avaliou os fatores que determinam a diastereosseletividade facial na arilação de Heck de enecarbamatos endocíclicos com sais de diazônio, foi desenvolvida a síntese total e estereosseletiva do C-azanucleosídeo de Schramm (uma pirrolidina sintética com potente atividade tripanocida). Este estudo ilustra a versatilidade de enecarbamatos endocíclicos como intermediários sintéticos na construção de moléculas mais complexas
Abstract: There was a great interest in the preparation of nucleosides and derivatives in the last years due to the large spectrum of biological activities of these substances. Several analoges with structural modifications have been reported in the literature, such as azanucleosides, where the oxigen atom of the glicosidic portion is replaced by a nitrogen. In the first part of this work, several five membered ring endocyclic enecarbamates, that are enantiomerically pure (chiral-GC), were obtained in seven steps sequence from L-glutamic acid and used in the synthesis of azanucleosides. In the second part of this work, the eletrophilic addition of phenylselenenyl bromide to endocyclic enecarbamates was used as the key step in synthesis of a unpublished series of N-azanucleosides (structurally related to the drugs presents in the anti-HIV cocktail). In the last step of this work, during a study to determinate the factors that command the facial diastereoselectivity on the Heck arylation of endocyclic enecarbamates with diazonium salts, a total and stereoselective synthesis of Schramm C-azanucleoside (a synthetic pyrrolidine with potent tripanocidal activity) was performed. These studies have show the versatility of endocyclic enecarbamates as synthetic intermediates to the building of more complex molecules
Doutorado
Quimica Organica
Doutor em Ciências
Vallin, Karl S. A. "Regioselective Heck Coupling Reactions : Focus on Green Chemistry." Doctoral thesis, Uppsala University, Department of Medicinal Chemistry, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3380.
Full textCarbon-carbon bond formation reactions are among the most important processes in chemistry, as they represent key steps in the synthesis of more complex molecules from simple precursors. This thesis describes mainly the development of novel regioselective applications of the mild and versatile palladium-catalyzed carbon-carbon coupling method, commonly known as the Heck reaction. In addition, this thesis will focus on environmentally friendly developments of the Heck reaction.
Novel ligand-controlled internal Heck vinylations of vinyl ethers and enamides to form branched electron-rich dienes were performed with high regioselectivity. The vinylation of 2-hydroxyethyl vinyl ether permits a chemoselective transformation of a vinylic triflate or bromide into a blocked α,β-unsaturated methyl ketone. Furthermore, a simple separation of the palladium catalyst was achieved with new fluorous-tagged bidentate ligands in combination with fluorous solid phase extraction. The reaction times could be reduced up to 1000 times with controlled microwave heating in the palladium-catalyzed reactions with, in the majority of cases, retained, high selectivity.
The development of a “green” regioselective arylation and vinylation method relying on an aqueous DMF-potassium carbonate system and excluding the toxic thallium salt has been accomplished. Ionic liquids as the versatile and environmentally friendly class of solvents have been used in rapid phosphine-free terminal Heck arylations with controlled microwave heating. Recycling of the catalytic medium was achieved after a simple product purification.
Sveen, Kim Andre. "EZ Running Belt eliminates heel-strike : Case series." Thesis, Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:gih:diva-2924.
Full textWestermann, Elke. "Ein neues phosphinfreies Katalysatorsystem für die HECK-Reaktion." [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=959496734.
Full textBöhm, Volker Peter Wilhelm. "Katalytische Aktivierung von Chloraromaten in der Heck-Kupplung." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=959981802.
Full textHeeg, Claus [Verfasser]. "Entwicklung eines Produktdatenmodells zur designorientierten Gestaltanalyse / Claus Heeg." Aachen : Shaker, 2005. http://d-nb.info/1186576073/34.
Full textHeep, Thomas [Verfasser]. "Funktionsintegriertes Drehwerkzeug zur Effizienzsteigerung kryogener Kohlendioxidkühlung / Thomas Heep." Düren : Shaker, 2019. http://d-nb.info/1198600306/34.
Full textGreen, Linus. "Development of an Automatic Heel Ulcer Prevention Mattress." Thesis, KTH, Maskinkonstruktion (Inst.), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210246.
Full textDetta examensarbete är en del i ett produktutvecklingsprojekt som initierats av Jack Spira. Dess syfte har varit att leverera ett koncept som automatiskt förhindrar trycksår på hälen hosvårdpatienter. Detta koncept kommer sedan utvecklas vidare i ett startup-företag och sedan förhoppningsvis integreras i vården. För att kunna utveckla ett koncept som förhindrar, eller drastiskt reducerar antalet, trycksår på hälar gjordes en grundlig förstudie. Studien inkluderar litteraturstudier för att förstå orsaker och mekanismer bakom trycksår samt en genomgång av befintliga behandlingar och förebyggande åtgärder. Efter en idégenereringsprocess bedömdes, diskuterades och sållades de olika idéerna inom projektgruppen. Det slutgiltiga konceptet är en madrass, kompatibel med befintliga vårdsängar, som med hjälp av sensorteknik och pneumatic helt avlastar patientens hälar och därmed förhindrar uppkomst av trycksår. Förfarandet är helautomatiserat för att utesluta den mänskliga faktorn och det behov av tidig upptäckt som finns i dagens metoder. Konceptet kommer att utvecklas vidare av det startup-företag som bildats av projektgruppen. Framtida planer innefattar bland annat prototyptillverkning för slutgiltig teknisk utvärdering och en klinisk studie för att kvantifiera dess potentiella inverkan på antalet trycksår som uppstår.
McGinnis, Elizabeth. "Heel pressure ulcers : a study of wound healing." Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/2802/.
Full textThompson, Nathan. "Heke te toa! How has Hone Heke Pokai, pictorially represented, contributed to the construction of New Zealand's national identity 1840-2005?" Thesis, University of Canterbury. Art History, 2006. http://hdl.handle.net/10092/880.
Full textNassar, Hardy Luma. "Tandem reactions using multi-task catalysts." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14317/document.
Full textThe development of clean chemistry and therefore sustainable is one of the major challenges of the 21st century in industrialized countries. Being in the heart of many discoveries in various scientific fields ranging from physics to medicine, the chemical sciences must play a central role in solving a number of environmental problems we face. My thesis work is part of this problem through the development of synthetic methodologies involving several transformations in the same reactor. We have developed the reaction sequences called HRC (for Heck-Reduction-cyclization) building on the multi-task of a palladium catalyst. This work allowed us to prepare a variety of functionalized heterocycles or compounds from which we can cite the oxindole, the indanones, or the naphthoxindoles. This work has resulted for the time four publications in peer-reviewed journals
Lingnau, Fee Isabelle [Verfasser], Günther [Akademischer Betreuer] Heeg, Günther [Gutachter] Heeg, and Patrick [Gutachter] Primavesi. "Theaterkritik : Praxis und Theorie ihrer produktiven Möglichkeiten am Beispiel Herbert Iherings / Fee Isabelle Lingnau ; Gutachter: Günther Heeg, Patrick Primavesi ; Betreuer: Günther Heeg." Leipzig : Universitätsbibliothek Leipzig, 2014. http://d-nb.info/1238600158/34.
Full textLustosa, Danilo Machado 1990. "Estudo da arilação enantiosseletiva de 3-pirrolinas N-protegidas via reação de Heck-Matsuda." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249861.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: A reação de Heck convencional consiste em uma reação entre olefinas e haletos de arila ou vinila catalisada por paládio. A variante Heck-Matsuda (HM) utiliza sais de arenodiazônio, mais reativos do que os respectivos haletos de arila ou vinila.. Por muito tempo a HM apresentava como principal limitação metodológica a ausência de uma versão enantiosseletiva. Em 2012, o grupo do prof. Carlos Correia relatou a primeira reação de Heck-Matsuda enantiosseletiva. Com o intuito de tornar esta metodologia uma ferramenta sintética mais robusta e compreender melhor esta reação, esta dissertação relata novos estudos de complexos de paládio quirais, não racêmicos, como sistemas catalíticos na arilação de 3-pirrolinas N-protegidas em reações de Heck-Matsuda enantiosseletivas. Com a utilização de complexos Pd/piridinoxazolina obteve-se adutos de Heck contendo substituintes doadores de elétrons em rendimentos de bons a excelentes e razões enantiômericas de moderadas a boas. Ao se fazer uso de sais de arenodiazônio com substituintes retiradores de elétrons, obteve-se os adutos de Heck em rendimentos de baixos a bons e razões enantiômericas de boas a excelentes. Alguns dos adutos de Heck foram selecionados e aplicados na obtenção de análogos do baclofeno e suas respectivas butirolactamas, com o objetivo de demonstrar a aplicabilidade sintética da nova metodologia e determinar a estereoquímica absoluta dos adutos de Heck obtidos (via comparação dos valores de [a]D obtidos com aqueles relatados na literatura). Por fim, com a estereoquímica dos produtos determinadas, racionalizou-se a obtenção destes adutos de forma enantiosseletiva através da apresentação de ciclos catalíticos apropriados
Abstract: The conventional Heck reaction consists of a reaction between olefins and vinyl or aryl halides catalyzed by palladium. The variant Heck-Matsuda (HM) uses arenediazonium salts, more reactive than the corresponding aryl or vinyl halides. For a long time the HM was seeing as a limited synthetic method due to the absence of its enantioselective version. In 2012, the group of prof. Carlos Correia reported the first enantioselective Heck-Matsuda reaction. Aiming at making this methodology a powerful synthetic tool, as well as to get mechanistic insights, this dissertation describes our studies on the enantioselective HM employing chiral, non-racemic, palladium complexes for the arylation of 3-N-protected- pyrrolines. With the use of Pd/pyridine-oxazoline complexes chiral Heck adducts were obtained containing electron rich substituents in good to excellent yields in enantiomeric ratios from moderate to good. When making use of arenediazonium salts with electron withdrawing substituents, the Heck adducts were obtaining in low from good yields in enantiomeric ratios from good to excellent. Some of the Heck adducts were selected in order to synthesize baclofen analogues and butyrolactams to demonstrate not only the applicability of the new method but also to determine the absolute stereochemistry of the Heck adducts (comparison of our [a]D values with those reported in the literature). Finally, with the absolute stereochemistry of the products determined, a rationale for this new enantioselective Heck-Matsuda was provided
Mestrado
Quimica Organica
Mestre em Química
Olofsson, Kristofer. "Regiocontrol in the Heck-reaction and fast fluorous chemistry." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2001. http://publications.uu.se/theses/91-554-4883-6/.
Full textHeep, Barbara Katharina [Verfasser]. "Struktur-Eigenschaftsbeziehungen in Kupfer- und Silberargyroditen / Barbara Katharina Heep." Mainz : Universitätsbibliothek Mainz, 2020. http://d-nb.info/1214310834/34.
Full textBruwer, Naomi. "Landskap en identiteit in Tikoes deur Henk van Woerden." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53484.
Full textENGLISH ABSTRACT: This study explores the way in which the construction of landscape interacts with the development of identity in Tikoes by Henk van Woerden. Taking the metaphor of traveling in Tikoes as vantage point, the coterminous development of the South African landscape and the characters' identities are explored. The study is placed in a theoretical framework by defining space, landscape and place, with specific reference to the interaction of landscape and identity, especially as portrayed in migrant literature. The difference between observation of space and the experiencing of landscape and place out of space through cultural processes are emphasized. It is postulated that these processes not only lead to the development of landscape and place out of space, but also contributes to the development of the characters' identities. Through an in-depth study of Tikoes, it is established that landscape and identity not only develop coterminously in this novel, but that these processes of development are actually interdependent. Tikoes, apparently a mere story about the journey of two lovers, is well constructed regarding the integration of themes and motives, which culminates in the cardinal interaction between observation and experience. The theme postulated by the motto is thus reflected in the structure of the novel: Let shallow people call me frivolous, when it comes to the point I have always been conscientiously precise.
AFRIKAANSE OPSOMMING: Die studie ondersoek die wyse waarop die konstruksie van landskap in wisselwerking tree met die ontwikkeling van identiteit in Tikoes deur Henk van Woerden. Met die reismetafoor binne Tikoes as uitgangspunt, word die samevallende ontwikkeling van die Suid-Afrikaanse landskap en die karakters se identiteite bestudeer. Die ondersoek word geplaas binne 'n teoretiese raamwerk oor ruimte, landskap en plek, met spesifieke verwysing na die verhouding tussen landskap en identiteit, soos veral verwoord in migranteliteratuur. Daar word onderskei tussen die waarneming van ruimte, en die gewaarwording van landskap en plek na aanleiding van die geografiese ruimte, deur kulturele prosesse. Dit word geponeer dat hierdie prosesse nie net lei tot die ontwikkeling van landskap en plek uit ruimte nie, maar ook bydra tot die ontwikkeling van die karakters se onderskeie identiteite. Deur 'n analise van Tikoes, word gevind dat landskap en identiteit nie net samevallend in dié roman ontwikkel nie, maar dat dié ontwikkelingsprosesse as't ware interafhanklik van mekaar staan. Tikoes, oënskynlik bloot 'n verhaaloor die reis van twee geliefdes, bied 'n deurgekomponeerdheid van temas en motiewe wat kulmineer in die kardinale wisselwerking tussen waarneming en gewaarwording, waardeur die roman die tema wat in die motto aangekondig word ook struktureel waar maak, naamlik: Laat de oppervlakkigen mij lichtzinnig noemen. Als het erop aankwam was ik altijd heel nauwgezet.
Heeg, Julian [Verfasser]. "Förderung diagnostischer Fähigkeiten angehender Chemielehrkräfte hinsichtlich Lernendenvorstellungen / Julian Heeg." Hannover : Gottfried Wilhelm Leibniz Universität, 2021. http://d-nb.info/1232405221/34.
Full textMcAlpine, Neil James. "Design and Development of New Aerobic Boron Heck Reactions." Thesis, Princeton University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10977124.
Full textTransition-metal catalyzed cross-coupling has, in many ways, revolutionized synthetic chemistry by providing streamlined syntheses using highly modular building blocks. Despite the widespread application of the Suzuki and Buchwald-Hartwig cross-coupling reactions, utilization of more contemporary cross-coupling protocols is narrower. Progress in applied research using transition- metal catalyzed reactions is often hampered by the necessity for unwieldy substrate syntheses. Seeking to tackle this problem, we have developed two novel C-C bond forming reactions in the context of the oxidative boron Heck reaction that converts simple starting materials into highly useful products which are directly applicable to many powerful synthetic protocols.
Firstly, an aerobic boron Heck reaction has been developed, which facilitates the conversion of feedstock olefins, namely, ethylene and propylene to styrenes and b-methylstyrenes using abundant (hetero)aryl boronic acids. The relevance to complex molecule synthesis is highlighted by a two-step synthesis of the pharmaceutical phenprocoumon.
Secondly, an aerobic boron Heck reaction of cyclobutene has been developed using abundant (hetero)aryl boronic acids. Instead of forming the classical Heck product (3-aryl-cyclobutene) a linear 1-aryl-1,3-diene is generated with complete chemo-, regio- and stereo-selectivity. 1-Aryl- 1,3-dienes have found myriad applications in modern transition-metal catalyzed cross-couplings however the substrates are often prepared by poorly efficient Wittig reactions. Both computational and mechanistic experimental data support a mechanism that proceeds by a classical Heck reaction followed by pericyclic ring opening mechanism for C-C bond cleavage. 1-Aryl-1,3,5-trienes were similarly prepared using alkenyl boronic acids.
Scherrer, Philipp [Verfasser]. "Das Parlament und sein Heer. : Das Parlamentsbeteiligungsgesetz. / Philipp Scherrer." Berlin : Duncker & Humblot, 2010. http://d-nb.info/1238363598/34.
Full textSilva, Juliana Sofia Gomes da. "Estudos da reacção de Heck em cinamilidenoacetofenonas com iodobenzenos." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/2975.
Full textEsta dissertação consiste no estudo da reactividade de (E,E)-cinamilidenoace-tofenonas em reacção de Heck com iodetos de arilo. Este estudo foi dividido em duas partes: primeiro foram usadas as condições de adição desenvolvidas por Cacchi e posteriormente testaram-se as condições desenvolvidas por Jeffery para a reacção de Heck. Este trabalho iniciou-se com o estudo da reacção de Heck nas condições de Cacchi para dois sistemas carbonílicos α,β- e α,β,γ,δ-insaturados, as (E)-calconas e as (E,E)-cinamilidenoacetofenonas, respectivamente. A reacção da (E)-calcona com iodobenzeno originou o produto de adição na posição β e os seus isómeros cis e trans, em bons rendimentos, no entanto, com as (E,E)-cinamilidenoacetofenonas não se verificou a formação de qualquer produto. A segunda parte do estudo consiste no estudo da reacção de Heck das (E,E)-cinamilidenoacetofenonas com iodetos de arilo nas condições de Jeffery, tendo-se obtido o produto de substituição na posição β com rendimentos baixos. A presença de diferentes grupos substituintes no anel B não mostrou qualquer alteração nos rendimentos dos produtos obtidos. A presença de um grupo dador de electrões no iodoareno provoca um ligeiro aumento no produto resultante da β-substituição. Na caracterização estrutural dos compostos sintetizados recorreu-se a técnicas analíticas actuais, em especial através de estudos de espectroscopia de ressonância magnética nuclear (RMN) [espectros de 1H, de 13C e estudos bidimensionais de correlação espectroscópica homo e heteronuclear e de efeito nuclear de Overhauser (NOESY)]. Os novos produtos obtidos foram igualmente caracterizados por espectrometria de massa. ABSTRACT: This dissertation reports the reactivity study of (E,E) –cinnamylideneacetophenones in Heck reaction with iodoarenes. This study is constituted by two parts: in the first part the Heck reaction under the Cacchi conditions was studied, while in the second part the Jeffery conditions were evaluated. This work started by the study of the Heck reaction, under the Cacchi conditions of α,β- and α,β,γ,δ-unsaturated carbonyl systems, (E)-chalcones and (E,E)-cinnamylideneacetophenones. The Heck reaction of (E)-chalcone with iodobenzene gives the product of conjugate adition, in good yields, however with (E,E)-cinnamylideneacetophenones there is no reaction. The second part of this study consists in the study of the Heck reaction with iodoarenes under Jeffery conditions, resulting in the substitution product at β-position of (E,E)-cinnamylideneacetophenone in low yields. The presence of different groups on B ring didn’t show any influence in the formation yields of β-substituted cinnamylideneacetophenones. The presence of an electron-donating group in the iodoarene allows a slightly increase in the β-substitution product formation. All the synthesised compounds were characterised using modern analytical techniques, with special emphasis on exhaustive nuclear magnetic resonance (NMR) spectroscopic studies [1H and 13C spectra, two dimensional homonuclear and heteronuclear spectroscopy and NOESY]. All the new compounds were also characterized by mass spectrometry.
Arditti, Roger Christopher. "'Our Achilles' heel' : interagency intelligence during the Malayan emergency." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/12842.
Full textNasr, Rachad. "Exploring MRP1 overexpression as "Achilles Heel" of chemoresistant cancers." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1006.
Full textMultidrug resistance Protein 1 (MRP1) is involved in the multidrug resistance (MDR) phenotype of cancer cells. Physiological substrates of MRP1 include glutathione (GSH) and drugs such as doxorubicin are co-transported with glutathione. To circumvent the MDR phenotype induced by MRP1, we propose a new therapeutic strategy based on collateral sensitivity (CS) of resistant cell expressing MRP1, its overexpression becoming the Achilles heel of the cell. Some compounds, like verapamil, act as MRP1 modulators. They trigger selective death of resistant cells (control cells are not affected) by stimulating MRP1-mediated glutathione efflux. The fast and huge intracellular depletion of glutathione probably induces an oxidative stress triggering cell death. We identified new potent collateral sensitivity agents in vitro and we checked the effect of the strongest compound on reducing resistant tumor growth in nude mice. We studied the molecular mechanism of action of CS agents and identified an unexpected residue involved in the stimulation of glutathione efflux induced by these molecules
Berg, Sören Lennart [Verfasser], Martin [Akademischer Betreuer] Henk, Martin [Gutachter] Henk, Cifre María A. [Gutachter] Hernández, and Raman [Gutachter] Sanyal. "Lattice points in convex bodies : counting and approximating / Sören Lennart Berg ; Gutachter: Martin Henk, María A. Hernández Cifre, Raman Sanyal ; Betreuer: Martin Henk." Berlin : Technische Universität Berlin, 2018. http://d-nb.info/1174990333/34.
Full textFragner, Stefan. "Die Einbeziehung des privaten Sektors im Bereich der U.S. Army - eine Bestandesaufnahme der wirtschaftlichen, rechtlichen und politischen Aspekte sowie Entwicklungstendenzen." Institut für Transportwirtschaft und Logistik, WU Vienna University of Economics and Business, 2005. http://epub.wu.ac.at/1172/1/document.pdf.
Full textSeries: Schriftenreihe des Instituts für Transportwirtschaft und Logistik - Logistik
Gleasure, A. J. "Ruthenium and palladium catalysed cyclisation reactions." Thesis, Queen's University Belfast, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246436.
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