Tesis sobre el tema "C-S bond formation"
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Arambasic, Milan. "Carbon-carbon bond formation via rhodium-catalysed C-S activation processes". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:e9e29a73-e637-4844-9a37-58b5ae4a3f99.
Texto completoGarcia, Civit Marc. "Activation of B-interElement (E=S, Se) reagents towards selective C-S and C-Se bond formation". Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/454746.
Texto completoEsta tesis describe el trabajo realizado con reactivos que contienen enlaces boro-azufre o boro-selenio. Estos reactivos se han usado en reacciones de tioboración y selenoboración de sustratos con insaturaciones conjugadas a cetonas o esteres y en reacciones de inserción con grupos diazo para sintetizar nuevos compuestos organosulfurados y organoselenados. La tesis se divide en cuatro capítulos. El primero es una breve introducción a los compuestos organosulfurados y organoselenados, hablando sobre sus principales aplicaciones y los métodos para sintetizarlos más representativos hasta el momento. En este primer capítulo también se presenta el método de síntesis de los reactivos de boro-azufre y boro-selenio y las reacciones en las que se han usado. El segundo capítulo habla de la reactividad de los compuestos de boro-azufre con cetonas y aldehídos α,β-insaturados. Se ha observado que el propio grupo carboxilo es capaz de activar el reactivo y hacer entrar la unidad de azufre en la posición beta. El tercer capítulo habla de la reacción con triples enlaces conjugado a cetonas y esters para sintetizar vinilo sulfatos y vinilo selenatos. Esta misma reacción en presencia de una fosfina permite obtener compuestos anti-3,4-selenoborats que son precursores de compuestos con el grupo selenio en la posición alfa. El último capítulo habla sobre las reacciones de inserción de compuestos diazo en el enlace boro-azufre que permite obtener moléculas muy funcionalizadas con los grupos Si, B, S y H que debido a sus diferentes propiedades químicas pueden continuar siendo funcionalizados.
This thesis describes the work done with reagents that contain links boron-sulphur or boron-selenium. These reagents have used in reactions of thioboration and selenoboration of substrates with unsaturation conjugated to ketones or esters and in reactions of insertion with diazo compounds to synthesize new organosulfides and organoselenides compounds. The thesis is divided in four chapters. The first is a brief introduction to the organosulfides and organoselenides compounds, reporting its main applications and its more representative methods of synthesis. The first chapter also reported the synthesis of the boron-sulphur and boron-selenium reagents and the reactions where they have been used. The second chapter is about the reactivity of the compounds of boron-sulphur with α,β-unsaturated ketones and aldehydes. It has observed that the carboxyl group is able to activate the B-S reagent and deliver the sulphur unit in the beta position. The third chapter shows the reactivity with triple bonds conjugated to ketones and esters to synthesise vinyl sulphates and vinyl selenates. The same reaction in presence of a phosphine allow to obtain anti-3,4-selenoborated compounds that they are precursors of compounds with the selenium moiety in the alpha position. The last chapter is about the insertion reactions of diazo compounds into the boron-sulphur bond that allow to obtain molecules very functionalized with groups Si, B, S and H than due to its different chemical behaviour can be further functionalized.
Vuong, Khuong Quoc Chemistry Faculty of Science UNSW. "Metal complex catalysed C-X (X = S, O and N) bond formation". Awarded by:University of New South Wales. Chemistry, 2006. http://handle.unsw.edu.au/1959.4/23015.
Texto completoFusillo, Vincenzo. "New insights into scale up processing and C-S bond formation reactions". Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/28635/.
Texto completoAota, Yusuke. "Development of New Methodologies for the Asymmetric Synthesis of Chiral Sulfoximines via C-S Bond Formation". Kyoto University, 2020. http://hdl.handle.net/2433/253103.
Texto completoGehrtz, Paul Henry [Verfasser] y Ivana [Akademischer Betreuer] Fleischer. "Pd- and Ni-based catalysts for mild C-S bond activation and formation / Paul Henry Gehrtz ; Betreuer: Ivana Fleischer". Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/120277394X/34.
Texto completoGehrtz, Paul [Verfasser] y Ivana [Akademischer Betreuer] Fleischer. "Pd- and Ni-based catalysts for mild C-S bond activation and formation / Paul Henry Gehrtz ; Betreuer: Ivana Fleischer". Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/120277394X/34.
Texto completoHuadsai, Wimonsiri. "Activation du dioxyde de carbone par des composés de Lewis hautement acidés". Electronic Thesis or Diss., Université de Toulouse (2023-....), 2024. http://www.theses.fr/2024TLSES053.
Texto completoThis research aimed to investigate the potential applications of Mg and Ca hydride complexes supported by ß-diketiminate and amidinate ligands for the reduction of CO2 molecules. The catalytic abilities of these complexes were explored in the context of hydroboration and hydrosilylation of CO2. In the first part of the study, we examined the reactivity of ß-diketiminato Mg and Ca hydrides with CO2. It was observed that the Mg hydride complex rapidly incorporated CO2, leading to the formation of various intermediates with different nuclearities. This involved the insertion of Mg—H bond into CO2, resulting in the generation of formate moieties. Under heat, hexameric formate complexes were formed through a "ligand flip" mechanism, releasing steric hindrances around the metal centers. For Ca hydride and CO2 reactions, in situ NMR analysis was mainly conducted. Additionally, a novel Mg amidinate dihydride complex was successfully synthesized and reacted with CO2 to yield a unique single product of dimeric formate Mg complex, in contrast to the ß-diketiminate scaffold, where several formate species were detected. The second part of the research focused on the catalytic hydroboration of CO2 using alkaline-earth hydride complexes. In particular, the Ca-based system demonstrated high efficiency in the production of the four-electron reduction of CO2 or BBA product. This was the first example of using Mg and Ca hydride compounds to catalyze the hydroboration of CO2, selectively producing the BBA product. The in situ generated BBA was further used as a methylene transfer reagent in condensation reactions with thiols, resulting in the formation of novel stable hemithioacetal [RS—CH2—OBR2] compounds under mild and neutral conditions. Activation of the hemithioacetal compounds was achieved under acidic conditions, leading to the formation of dithioacetals and hemithioaminals. The condensation of the second OBR2 fragment with secondary amines, which act as stronger nucleophiles, resulted in the generation of aryl methyl sulfides [RS—CH2—NR2]. In the final section, we investigated the tandem hydrosilylation of CO2 using various hydrosilanes in combination with [Ae]-based hydride complexes and Lewis acid B(C6F5)3 as catalysts. This research expanded on previous studies of Mg-mediated hydrosilylation of CO2 and introduced the first example of Ca-catalyzed CO2 hydrosilylation with hydrosilanes. The effectiveness of reducing CO2 to CH4 or bis(silyl)acetal [H2C(Ph3SiO)2] or BSA depended on the nature of the silanes and the steric hindrances around the substrate Si—H bond. The choice of [Ae] catalyst also significantly influenced the overall reaction rate. Furthermore, Eyring and Arrhenius analyses provided insight into the activation parameters for reducing CO2 by certain catalysts, revealing that this reaction is primarily governed by an entropic contribution. In summary, this research has demonstrated the reactivity of Mg and Ca hydride complexes for CO2 reduction and explored their applications in hydroboration and hydrosilylation reactions. Future investigations may explore mechanistic possibilities, kinetic differences, and the reactivity of group 2 metal hydride complexes with carbon monoxide for CO homologation
Roberts, Deborah Elizabeth. "Palladium N-neterocyclic carbene complexes as catalysts for C-N, C-Si and C-S bond formations". Thesis, University of Sussex, 2013. http://sro.sussex.ac.uk/id/eprint/45342/.
Texto completoThakur, V. V. "Asymmetric synthesis of bioactive molecules and formation of C-C, C-N, C-Br, S-O bonds by transition metal catalysis". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2002. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2338.
Texto completoJia, Fan [Verfasser], Lukas J. [Gutachter] Gooßen y Gerald [Gutachter] Dyker. "Catalytic methods for C-C, C-N and C-S bond formations / Fan Jia ; Gutachter: Lukas J. Gooßen, Gerald Dyker ; Fakultät für Chemie und Biochemie". Bochum : Ruhr-Universität Bochum, 2018. http://d-nb.info/1165304686/34.
Texto completoNookaraju, U. "Studies directed towards the synthesis of polyketides, lactones, mono acetogenins and development of new methodologies involving C-S and C-N bond formations". Thesis(Ph.D.), CSIR - National Chemical Laboratory, Pune, 2016. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2093.
Texto completoChen, Tzu-ming y 陳姿旻. "C-S bond formation via cross coupling reactions by copper catalysts". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/02628576949657378059.
Texto completo國立中正大學
化學所
96
Recently, cross-coupling reactions (including C-S bond, C-O bond and C-N bond formation) attracted great attention, because of their versatile possibilities of biological, pharmaceutical and material applications, thus we focus on C-S bond formation in this thesis. Copper catalyzed cross-coupling reaction is a remarkable and economic method of C-S bond formation, and we prepared two different copper complexes as the catalysts of cross-coupling reactions. We performed the cross-coupling reactions with three conditions: (1) aryl halides and thiophenols were dissolved in toluene and heated in a 120℃ oil bath under nitrogen atmosphere; the highest yield was 91.8%. (2) aryl halides and thiophenols were dissolved in water and heated to 80℃ under air; the reactions were nearly inactive. (3) phenylboronic acids and disulfides were dissolved in water/1,4-dioxane (1:2) and heated to 100℃ under air; the highest yield was 73.7%.
Chen, Yi-Ling y 陳以鈴. "1. CuI/Oxalic Diamide-Catalyzed Cross-Coupling of Thiols with Aryl Chlorides2. Application of C-S Bond Formation on Vortioxetine Synthesis". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/99b5d6.
Texto completo國立中興大學
化學系所
106
In the first part of this thesis, we report a general copper-catalyzed cross-coupling of thiols with aryl chlorides by using N,N''-dialkyl oxalic diamide (L5) as the ligand. Both aryl- and alkyl thiols can be coupled with unactivated aryl chlorides to give the desired products in good yields for the first time. Furthermore, this system features broad substrate scope and good tolerance of functional groups. Importantly, the oxalic diamides are stable and can be prepared easily from commercially available cheap starting materials. The second part of this thesis, application of this copper-catalyzed cross-coupling of 2,4-dimethylyhiophenol with 1,2-diiobenzene by using N,N''-dialkyl oxalic diamide (L5) as the ligand has been described for the synthesis of antidepressant Vortioxetine.
Hannoun, Kareem Imad. "Mechanistic Study of Cu-Mediated, Photoinduced C–S Bond Formation and Demonstration of Electrochemical Ammonia Production by a Surface-Attached Iron Complex". Thesis, 2019. https://thesis.library.caltech.edu/11565/27/Hannoun_Thesis_A.pdf.
Texto completoThe worldwide reliance on fossil fuels for energy and petrochemicals poses a massive environmental hazard. Furthermore, many chemical processes rely on precious metals that have low abundance on Earth and are threatened. As the world population grows rapidly, these factors pose an increasing threat to our planet and new chemical processes are needed that employ earth-abundant catalysts and alternative chemical currencies such as light and electricity derived from renewable sources.
Chapter 2 discusses an in-depth mechanistic study of the photoinduced, copper-mediated cross-coupling of aryl thiols with aryl halides. This reaction employs light energy and an earth-abundant metal to achieve bond formation through a pathway distinct from that of thermal reactions. In particular, I focus on the stoichiometric photochemistry and subsequent reactivity of a [CuI(SAr)2]– complex (Ar = 2,6-dimethylphenyl). A broad array of experimental techniques furnish data consistent with a pathway in which a photoexcited [CuI(SAr)2]-* complex undergoes SET to generate a CuII species and an aryl radical, which then couple through an in-cage radical recombination.
Chapter 3 discusses the surface attachment of a P3BFe complex to a carbon electrode, and the electrochemical generation of ammonia from N2 by the surface-appended species (P3BFe = tris-phosphinoborane). Ammonia production is achieved industrially by the combination of N2 and H2, the latter of which is derived from methane with concomitant production of CO2. Alternative chemical processes, such as the use of energy derived from electricity, are vital for the decreasing the carbon footprint of ammonia production. Synthetic modification of a previously-reported P3BFe complex by addition of three pyrene substituents onto the catalyst backbone allows non-covalent attachment onto a graphite surface. The resulting functionalized electrode shows good stability towards iron desorption under highly reducing conditions, and produces 1.4 equiv NH3 per iron site. The data presented provide the first demonstration of electrochemical nitrogen fixation by a molecular complex appended to an electrode.
Li, Chao-En y 李兆恩. "1.Investigation of Copper-Catalyzed Intramolecular Thiolation Reaction by Using Sulfur Powder2.Palladium-Catalyzed Decarbonylative C−S Bond formation from Thioester to Thioether". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/xaubgq.
Texto completo國立中興大學
化學系所
106
In the first part of this thesis, we report a convenient and efficient approach via copper-catalyzed thiolation of imidazo[1,2‐a]pyridines with sulfur powder, the reaction condition is under ligand-free and solvent-free, 14 examples were reported up to 98% yield. In the second part of this thesis, we reported a palladium-catalyzed decarbonylation C-S cross coupling reaction to convert thioester to thioether. In the present protocol a variety of electron-withdrawing and electron-donating group have been used and they can all proceed well in this protocol, even the alky group can get the result up to 50% yield. This process demonstrates a novel and efficient strategy to synthesize thioether.
Du, Kai y 杜凱. "1.Investigation of Blue LEDs Promoted Synthesis of Dithioacetals2.Investigation of Blue LEDs Promoted Formation of C-S Bond of Aryl Amines with Thiols". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/z5fzmt.
Texto completo國立中興大學
化學系所
106
In the first part of this thesis, we achieve a simple and elegant method for dithioacetalization of aldehyde using blue LEDs irradiation under photochemical reaction. The salient features of this method are broad substrate scope and good tolerance of electron donating and withdrawing group, metal free and solvent free conditions. It is noteworthy that our present protocol is eco-friendly in nature and we will develop LEDs promoting reaction in future green chemistry avenues. In the second part of this thesis, we achieve a simple method for thiol ether formation of aryl amines and thiols using blue LEDs irradiation under photochemical reaction. This project is metal free, solvent free and eco-friendly in nature.
Vithalrao, Paike Vijaykumar y 派克. "Use of Tetrabutylammonium Fluoride (TBAF) as an Effective Organocatalyst for the Formation of C-C, C-N and C-S bonds". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/24183437076503097067.
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