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Copper Catalysis: Perfluoroalkylation and Atom Transfer Radical PolymerizationPaeth, Matthew S. 22 September 2021 (has links)
No description available.
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Synthèse et fonctionnalisation directe catalytique de la liaison C-H d'imidazolones : nouvel accès aux fluorophores analogues de la GFP / Synthesis and direct, catalytic functionalization of the C-H bond of imidazolones : novel access towards GFP-like fluorophoresMuselli, Mickaël 19 July 2017 (has links)
Les imidazolones sont des molécules étudiées de longue date, soit en tant que molécules bioactives, soit pour leurs propriétés de fluorescence, l'exemple le plus connu étant la GFP. De nombreuses synthèses étaient déjà décrites, en particulier la condensation d'une amine avec une oxazolone (méthode d'Erlenmeyer). Au cours de ce travail, nous avons non seulement amélioré le protocole d'Erlenmeyer, mais surtout développé une synthèse originale consistant à utiliser l'arylation C-H de 2-H imidazolones. Dans cet objectif, il a fallu tout d'abord mettre au point un protocole de synthèse des 2-H imidazolones, jusqu'alors très peu décrites, puis mettre au point les conditions d'arylation et de vinylation directe de ces molécules. Deux séries d'imidazolones ont été étudiées et publiées séparément : en premier lieu, les 4,4'-dialkyl-imidazolones, fréquemment employées pour leurs propriétés biologiques, puis, au cours du travail qui a suivi, l'arylation et la vinylation des 4- arylidène-2-H imidazolones. / Imidazolones have been studied for a long time, either as bioactive molecules or for their fluorescence properties, the best known example being the Green Fluorescent Protein or GFP. Numerous syntheses are already described, in particular the condensation of an amine with an oxazolone (Erlenmeyer method). In this work, we not only improved the condensation protocol but also developed an original synthesis consisting in using 2-H imidazolones CH arylation. To this end, it was first necessary to develop a protocol for the synthesis of 2-H imidazolones, hitherto very little described, and then to develop the conditions for arylation and direct vinylation of these molecules. Two sets of imidazolones have been studied and published separately: first, the 4,4'- dialkylimidazolones, frequently used for their biological properties, followed by arylation and vinylation of 4-arylidene-2-H imidazolones.
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Palladation et fonctionnalisation de pyrimidinones et d'imidazolones / Palladation and functionalization of pyrimidinones and imidazolonesCollado Ruiz, Sandra 03 December 2018 (has links)
Depuis ces dix dernières années, notre laboratoire a développé une expertise dans le domaine de la fonctionnalisation de liaisons carbone-hydrogène (dite fonctionnalisation C-H) d’hétérocycles par catalyse aux métaux de transition. Le sujet de thèse s’inscrit dans un programme de recherche dirigé vers les hétérocycles pro-aromatiques à système N-acylamidine. Les travaux antérieurs ont porté sur les 4-alkyl et 4-arylidène imidazolones avec la production de nouvelles sondes GFP. Le présent travail de thèse vise à poursuivre le développement méthodologique en série pyrimidin-4-ones,encore très peu concernée dans ce domaine de recherche. Une méthode d’arylation C2-H de lapyrimidin-4-one substituée sur l’atome d’azote par divers chélates directeurs a été mise au point en utilisant une catalyse coopérative Pd(0)-Cu(I) et des halogénures d’aryles comme partenaires de couplage. L’étendue de la réactivité a été examinée de façon exhaustive puis la méthodologie a été évaluée pour l’arylation C2-H d’analogues structurels fonctionnalisés en positions C5. Une seconde étude s’inscrit dans le projet de rigidification des sondes GFP à coeur 4-arylidène imidazolone. Un travail préliminaire d’ortho-palladation C-H a été effectué en collaboration avec le Dr Esteban Urriolabeitia de l’université de Saragosse en Espagne. Les propriétés photophysiques des palladacycles originaux ainsi préparés ont été déterminées et leurs réactivités aux agents de couplage et aux oxydants évaluées. / Since past decade, our laboratory is concerned with transition-metal catalyzed C-H functionalization of heterocycles. A recent research program is dedicated to the class of N-acyl amidine pro-aromatic heterocycles. This present thesis work is first directed to the pyrimidin-4-one series that remains highly sparsely evaluated. As main results, Pd(0)-catalyzed and Cu(I)-assisted C2-H arylation of pyrimidin-4-one flanked with picolinyl and other ortho-directed groups at the nitrogen atom was set up using arylhalides as coupling partners. The C5-substituted pyrimidin-4-ones were also evaluated. To pursue recent investigations in 4-alkyl and 4-arylidene imidazolone series leaing ding to innovative GFP probes, the second work aims at evaluating the first step of an ultimate intramolecular C-H/C-H coupling to stiffen the 4-arylidene imidazolone core. For that, the intramolecular ortho-palladation was achieved in collaboration with Dr. Esteban Urriolabeitia of the University of Zaragoza in Spain providing a broad panel of original imidazolone-based palladacycles. Their photophysical properties were determined and their reactivity towards cross-coupling as well as oxidating agents were also evaluated.
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Stereoselective Radical Transformations with In Situ-Generated Aryl and Alkyl Diazomethanes via Co(II)-Based Metalloradical CatalysisWang, Yong January 2018 (has links)
Thesis advisor: X. Peter Zhang / Among recent advances in devising different strategies for stereoselective homolytic reactions, metalloradical catalysis (MRC) has emerged as a conceptually new approach for controlling stereoselectivity of radical reactions. As stable metalloradicals, cobalt(II) complexes of D₂-symmetric chiral amidoporphyrins [Co(D₂-Por)] have proven to be effective catalysts for homolytically activating a series of diazo compounds to generate α-Co(III)-alkyl radicals for various C-centered radical transformations with well-confined reactivity and selectivity. Nevertheless, the applications of donor-, donor/donor- and alkyl diazo compounds have been largely underdeveloped. This dissertation mainly focuses on how the chemistry of these types of diazo compounds was initiated by using commonly available aldehyde-derived sulfonylhydrazones as diazo surrogates. In the context of Co(II)-MRC, in situ-generated diazo compounds can be effectively activated for various asymmetric radical transformations, including intermolecular radical cyclopropanation of alkenes and intramolecular radical alkylation of C–H bonds. First, as a proof of concept, we have demonstrated the feasibility of using aryl aldehyde-derived sulfonylhydrazones as new radical precursors for diastereo- and enantioselective radical cyclopropanation of alkenes, and proven that the diazo in situ-generation protocol is well compatible with the catalytic radical process. Second, we have expanded the application of Co(II)-based MRC to a new territory by employing aliphatic diazo compounds for asymmetric cyclopropanation. The system is highlighted by the excellent enantioselectivity together with remarkable cis-selectivity. Finally, with the utilization of linear aliphatic aldehyde sulfonylhydrazones as diazo precursors, we have presented a new radical cyclization mode, involving hydrogen atom abstraction and radical substitution, for enantioselective synthesis of common five-membered rings via radical C–H alkylation. The system would offer a new retrosynthetic paradigm for construction of ring structures, where C–C bond can be disconnected as common C=O and C–H units of linear aldehydes. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
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C–H Activation by Iron(III), Manganese(II) and Rhoda(III)electro CatalysisShen, Zhigao 02 December 2020 (has links)
No description available.
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Catalytic Nitrene Reactions Enabled By Dinuclear Nickel CatalystsJohn M Andjaba (11155014) 23 July 2021 (has links)
<div><p>Nitrenes are reactive
intermediates that are known to generate high interest organic molecules. Due
to their inherent instability, nitrenes are often stabilized by introducing them
to transition metal complexes. Many transition metal stabilized nitrenes (M=NR<sub>2</sub>)
have been reported and some of these complexes have been shown to control nitrene
reactivity and selectivity. Transition metal nitrene reactivity can be
categorized into two main groups: bond-insertion and group transfer reactions.
In the reference to the former, chapter one of this dissertation highlights
using unique dinuclear Ni<sub> </sub>catalysts to generate nitrenes from
aromatic azides. These Ni<sub>2</sub> nitrenes are used towards selective C(sp<sup>2</sup>)−H
bond amination in order to
generate indole and carbazole derivatives. This work highlights the unique
properties of the Ni<sub>2</sub> imide that enable a 1,2-addition
pathway, which contrasts
known bimetallic nitrene insertion reactions. A detailed mechanistic study,
primarily using density functional theory (DFT) is the focus of this chapter.</p>
<p>Chapter two of this dissertation focuses on nitrene group
transfer. In particular, this chapter highlights the ability of the dinuclear
Ni<sub> </sub>catalyst [<i><sup>i</sup></i><sup>-Pr</sup>NDI]Ni<sub>2</sub>(C<sub>6</sub>H<sub>6</sub>)
to react with aromatic azides to perform N=N coupling. A large scope of functional
groups are tolerated in high yield with short reaction times. Catalyst
comparison studies, studies on relevant catalytic intermediates for N=N
coupling and reaction kinetics are shown in this chapter. Lastly, chapter three
showcases the expansion of the nitrene group transfer ability of [<i><sup>i</sup></i><sup>-Pr</sup>NDI]Ni<sub>2</sub>(C<sub>6</sub>H<sub>6</sub>) to generate high
molecular weight azopolymers from aromatic diazides. These azopolymers are
generated from monomers often used in organic semi-conducting materials. End
group control and post polymer functionalization are highlighted in this
chapter. Lastly, this work showcases a new polymer, polyazoisoindigo, as the
first organic semiconducting material that reversibly transitions from a colored
to colorless state upon reduction.</p><br></div>
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Iron-Catalyzed C–H/N–H Activations for Annulation of Allenes, Alkynes, and BicyclopropylidenesMo, Jiayu 26 October 2020 (has links)
No description available.
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カスケード型パラジウム触媒反応を利用した芳香族化合物の効率的合成南條, 毅 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(薬科学) / 甲第18915号 / 薬科博第29号 / 新制||薬||4(附属図書館) / 31866 / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 竹本 佳司, 教授 高須 清誠, 教授 大野 浩章 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
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Electrooxidative C-H Functionalization of Aromatic Compounds Based on Rational Design / 合理的設計に基づく電解酸化を用いた芳香族化合物のC-H官能基化Morofuji, Tatsuya 25 January 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19407号 / 工博第4123号 / 新制||工||1636(附属図書館) / 32432 / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 吉田 潤一, 教授 松田 建児, 教授 松原 誠二郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Pd触媒による分子内アリル位アミノ化および分子内C-H官能基化反応の開発末次, 聖 23 March 2017 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(薬科学) / 乙第13086号 / 論薬科博第2号 / 新制||薬科||9(附属図書館) / (主査)教授 竹本 佳司, 教授 高須 清誠, 教授 川端 猛夫 / 学位規則第4条第2項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
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