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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.
71

Příprava a katalytické vlastnosti ferrocenofanových fosfinů / Synthesis and catalytic properties of ferrocenophane phosphines

Škoch, Karel January 2012 (has links)
6 Title: Sythesis and catalytic properties of ferrocenophane phosphines Author: Karel Škoch Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Keywords: ferrocene, ferrocenophane, phosphine ligands, palladium, asymetric catalysis, aza- Morita-Baylis-Hillman reaction, asymetric allylic alkylation Abstract: This Thesis describes the preparation of five sterically and electronically different ferrocene phosphines, (R)-1,1'-[1-(diarylphosphino)propan-1,3-diyl]ferrocenes (R)-1a-e, and a study into their coordination and catalytic properties. The key precursor of the phosphine synthesis, chiral alcohol (R)-2, was prepared according to the procedure described in the literature. Alcohol (R)-2 was converted with retention of configuration to diarylphosphines (R)-1a-e in one-step reaction with trimethylsilylchloride and sodium iodide and then with the corresponding diarylphosphine. Phosphines 1a-e were characterized by NMR and MS methods. For the basic representative 1a the following palladium(II) complexes were prepared: [PdCl(LNC )(1a)] (10, LNC = 2-[(dimethylamino)methyl]phenyl-C1 ,N) and trans- [PdCl2(1a)2] (9a). In addition, the isomeric complex cis-[PdCl2(1a)2] (9b) was isolated from the reaction mixture after catalytic...
72

(S)-2-hidroxipropanoato de 2-N, N-dimetilaminoetila: síntese e investigação da atividade organocatalítica na reação de Morita-Baylis-Hilman. / (S)-2-hydroxypropanoate 2-N, N-dimetilaminoetila: Research synthesis and activity organic catalytic the reaction of Morita-Baylis-Hillman.

Silva, Wagner André Vieira da 28 August 2012 (has links)
Made available in DSpace on 2015-05-14T13:21:17Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 2697470 bytes, checksum: 43857465b95f5bc745fef7fb91591233 (MD5) Previous issue date: 2012-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study was performed in order to synthesize and evaluate a new chiral tertiary amine, (S)-2-hydroxypropanoate 2-N, N-dimetilaminoetila according to the concept of multifunctional catalyst, which allows one same molecule presents various characteristics such as Bronsted acid and Lewis base. Allied to the interests of organocatalysis of simplicity and low operating costs, resulting in products that do not have contaminants like metals, designed in order to be able to catalyze / promote the reaction of Morita-Baylis-Hillman (MBH). The synthesis was performed starting from cheap raw materials and good commercial availability, S-lactic acid and 2-N, Ndimetilaminoetan-1-ol in one step reaction (98%). Based on current mechanistic proposal of the MBH reaction, the mechanism of Cantillo and Kappe, we investigated the reaction conditions, where there is a hydrogen transfer in aprotic media and also in the presence of phenols as additives, checking the influence speeds, reaction yields and asymmetric induction. We investigated the reaction between pnitrobenzaldehyde and acrylonitrile as reaction MBH pattern, varying experimental conditions such as solvent, quantity of (S)-2-hydroxypropanoate 2-N, Ndimetilaminoetila time, temperature and addition of phenolic additives. In addition, a new method was developed for the separation of enantiomers for the racemic compound antiparasitic 2 - [Hydroxy (4-nitrophenyl) methyl] acrylonitrile by gas chromatography with high resolution capillary columns packed with chiral phases. Chemical yields were obtained 2 - [hydroxy (4-nitrophenyl) methyl] <1 to 98% and enantiomeric excesses up to 20.5%. Mechanistic aspects are discussed in this paper, based on the results and computations, using the theory DFT and QTAIM. / Este trabalho foi realizado com o intuito de sintetizar e avaliar uma nova amina terciária quiral, o (S)-2-hidroxipropanoato de 2-N,N-dimetilaminoetila de acordo ao conceito de catalisador multifuncional, o qual permite que uma mesma molécula apresente várias características como os de ácido de Bronsted e base de Lewis. Aliado aos interesses da organocatálise de simplicidade e baixo custo operacional, resultando em produtos que não apresentam metais como contaminantes, projetamos no intuito de ser capaz de catalisar/promover a reação de Morita-Baylis-Hilman (MBH). A síntese de foi efetuada a partir de matérias-primas baratas e de boa disponibilidade comercial; o ácido S-lático e o 2-N,Ndimetilaminoetan- 1-ol em uma etapa reacional (98%). Baseado na atual proposta mecanística da reação de MBH, o mecanismo de Cantillo e Kappe, foram investigados as condições reacionais, onde há a transferência de hidrogênio em meio aprótico e também na presença de fenóis como aditivos, verificando a influência nas velocidades, rendimentos de reação e indução assimétrica. Investigamos a reação entre o p-nitrobenzaldeído e a acrilonitrila como reação de MBH padrão, variando condições experimentais como: solvente, quantidade do(S)-2-hidroxipropanoato de 2-N,N-dimetilaminoetila, tempo, temperatura e adição de aditivos fenólicos. Em adição, foi desenvolvido um novo método de separação de enantiômeros para o composto racêmico antiparasitário 2-[Hidroxi(4-nitrofenil)metil] acrilonitrila via cromatografia gasosa com colunas capilares de alta resolução empacotadas por fases quirais. Foram obtidos rendimentos químicos do 2-[Hidroxi(4- nitrofenil)metil] <1 à 98% e excessos enantioméricos até 20,5%. Aspectos mecanísticos são discutidos neste trabalho, baseados nos resultados obtidos e em cálculos computacionais, usando a teoria DFT e QTAIM.
73

不飽和カルボニル化合物への共役付加を基盤とする選択的反応の開発

百武, 龍一 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(薬科学) / 甲第19661号 / 薬科博第49号 / 新制||薬科||6(附属図書館) / 32697 / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 川端 猛夫, 教授 高須 清誠, 教授 竹本 佳司 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM

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