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Showing 1 to 11 of 11 for “"Pauson-Khand Reaction"”.
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Expansion of the scope of the allenic Pauson-Khand reaction to include carboxylic acids and esters
… allenes were prepared by performing an SN2' reaction of lactones. Opening of the lactone created carboxylic acids that could then be converted to esters. By varing the functionality on the lactone and the Grignard reagents, a variety of allenes could be prepared to test the viability of the …
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Synthesis of P-Stereogenic Bisphosphine Ligands: Application as Hemi-labile Ligands in the Asymmetric Pauson-Khand Reaction
… of their use in a Co-catalysed asymmetric Pauson-Khand reaction has been carried out. The ligands were synthesised by asymmetric lithiation of a phosphine sulfide or a phosphine borane using alkyllithium/()-sparteine complexes, trapping with Ph2PCl or t-Bu2PCl and treatment with BH3•Me2S …
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Coordination Chemistry of Bis(diphenylphosphino)amine Ligands with Cobalt Carbonyl and the Intermolecular Catalyzed Pauson-Khand Reaction
… 2, the compounds show activity for the catalytic Pauson-Khand reaction, whereas when the PNP ligand bridges, as in 3, the reaction precedes stiochiometrically. The use of these chiral ligands has not yet resulted in enantioselective catalytic Pauson-Khand cycloadditions. However, a small 15% e.e. …
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Applications of titanium-mediated reductive coupling and cyclocarbonylation reactions toward natural product synthesis
… of tandem reductive cyclization - carbonylation reactions in the preparation of complex molecules but also the interesting stereoselectivity observed therein. The first part of this work employs the titanium-mediated cyclocarbonylation of tethered dienals for the synthesis of prostaglandin …
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Nanopartikuläre Katalysatoren und neue katalytische Anwendungen auf Basis der Metalle Rhodium und Cobalt
… be synthesised and tested in various catalytic reactions, as there are hydrogenation and C-C bond forming reactions (Pauson Khand reaction PKR). Additionally an effective protocol for the separation of the catalyst from the reaction solution was set up by immobilisation of the PEG-stabilised …
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Organocobalt Mediated Cyclizations and Biochemically Inspired Isomerizations - Method Development and Mechanistic Studies.
… literature from the early to mid-2010s of the Pauson-Khand Reaction(PKR). Chapter two focuses on our work utilizing x-ray absorption spectroscopy(XAS) to characterize reaction in- termediates of the intermolecular PKR. Chapter three highlights our group's work developing the use of N 2 O as a …
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Asymmetrische Synthese von bicyclischen Alpha-Aminosäuren durch intramolekulare Pauson-Khand-Reaktion von l-Alkenylsulfoximinen und Festphasensynthese mit Allylsulfoximinen
… atom gave 5-Azaoct-1-en-7-ynes in 91-95% yield. Pauson-Khand Reaction of these Enynes with Co2(CO)8 activated by N-Morpholine-N-oxide (NMO) afforded hexahydrocyclopenta[c]pyridine carboxylic acids with high selectivity (dr up to 98:2) and moderate yields (49-60%). The sulfoximine moiety was …
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Transition-metal catalysis of cyclocarbonylation and cycloisomerization reactions
Chapter 1. The asymmetric Pauson-Khand cyclization of nitrogen-containing enynes using carbon monoxide and a catalytic amount of (EBTHI)TiMe2 was examined. The influence of the nitrogen substituent and the concentration of the catalyst on the enantioselectivity of this cyclization was explored. It …
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Synthetic Studies Of Biologically Active Molecules: Irl 2500, Bruceantin, And Biliatresone
… bruceantin, we proposed to develop a homologous Pauson Khand reaction utilizing a strained bicyclic compound to generate bridged cyclohexenones via a [3+2+1] cycloaddition as a possible method to generate the bruceantin ring system. The synthesis of suitable bicyclic substrates for this reaction …
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A synthetic and computational approach to the design of new photoactive organometallic materials.
… to Sonogashira-Hagihara type cross coupling reactions. This is then followed by a literature survey on the synthesis and photochemistry of luminescent organometallic dyad systems. The synthesis of these novel systems using the Sonogashira-Hagihara method is described. The photophysical …
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Katalytische Festphasensynthese in Gegenwart von komprimiertem Kohlendioxid
… of compressed carbon dioxide on catalytic reactions on solid support was investigated. Pauson-Khand reactions (PKR) and hydrogenations were investigated representing reactions with gaseous substrates while the Baylis-Hillman reaction (BHR) was chosen because of its high negative reaction …