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Showing 1 to 13 of 13 for “"Tetrahydrofurans"”.
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Enantioselective synthesis of 2,2,5-Tri- and 2,2,5,5-tetrasubstituted tetrahydrofurans and synthesis of diketopiperazine containing natural products
… transformed into tetrasubstituted tetrahydrofurans via ring-opening metathesis/cross-metathesis or oxidative cleavage and refunctionalization. A partial synthesis of the bioactive diketopiperazine containing natural product gliocladin C was achieved in nine steps, and 13.4% overall …
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Application of sulfonimidoyl substituted allyltitanium (IV) complexes to the asymmetric synthesis of alkenyloxiranes, 2,3-dihydrofurans, tetrahydrofurans, unsaturated proline analogues and allylic alcohols
… of 2,3-dihydrofurans and of unsaturated bicyclic tetrahydrofurans from allylic sulfoximines and aldehydes is described in chapter 2.
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Part 1. Diaziridinium Ions: First Reported Synthesis and Reactivity Studies. Part 2. Tropylium Ion Mediated alpha-Cyanation of Amines. Part 3. Multicatalytic Synthesis of Complex Tetrahydrofurans
The first synthesis and full characterization of a new functionality, called the diaziridinium ion, is reported. The original synthetic intent behind its design was to explore its potential use as a non-metal based N-transfer reagent. During this study, we have uncovered a practical rearrangement …
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Asymmetrische Synthese funktionalisierter Homoallyl- und Homopropargylalkohole mittels der Sulfoximin-Route
… acetals yielded optically pure tetrasubstituted tetrahydrofurans.
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TEMPLATE DIRECTED C-H INSERTION REACTIONS FOR STEREOCONTROLLED SYNTHESIS OF HETEROCYCLES
… successful synthesis of 2,3,4,5-tetrasubstituted tetrahydrofurans and 2,3,4,5,6-pentasubstituted oxepanes. The key step involves catalytic C-H insertion of diazocarbonyl acetal templates. Diazocarbonyl substrates representing the three classes of carbenoids were synthesised. In the foremost route …
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The chemistry of 1,2-dioxines.
… was found giving rise to highly substituted tetrahydrofurans. Both l,2-dioxines and trans-γ-hydroxyenones could be used as starting materials for the dimerisation. The reaction mechanism was proposed to be an oxy-Michael / Michael cyclisation reaction giving the observed tetrahydrofurans. The …
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The effects of ancillary ligand properties on the reactions of rhodium diphosphine alkoxo alkene complexes
… at either 35 °C or 70 °C. The reactions produced tetrahydrofurans and rhodium hydrido complexes by a mechanism involving alkene insertion into the rhodium alkoxo bond and β-hydrogen elimination. The reactions were monitored by 1H NMR spectroscopy, and the rate constants for insertion of the alkene …
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Applications of C₂-symmetric bis(azaferrocenes) in asymmetric copper-catalyzed reactions
… catalyzes the ring expansion of oxetanes into tetrahydrofurans with high stereoselection. In the optimization process, we have developed a new hindered diazo ester that may also prove useful in other asymmetric carbene transfer processes. With the catalyst controlling the stereochemistry of the …
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I. Radical Cyclizations Mediated by Transition Metal Hydrides II. Study toward the Total Synthesis of Pluraflavin A III. Cytoprotective Polyacetylenes Inspired by Panaxytriol
… method was expanded to include the synthesis of tetrahydrofurans by employing vinyl ethers as substrates. The second part of the thesis describes study toward the total synthesis of the highly potent anti-proliferative natural product pluraflavin A. Synthesis of the optically active …
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Formation of 2,5-trans-tetrahydrofuran-3-one application towards the synthesis of natural products
… an efficient method for the synthesis of trans-tetrahydrofurans. Using this methodology, 5-hydroxy-1-alkenes can be converted to the desired cyclisation product via oxidative cyclisation with molecular oxygen using cobalt complex as a catalyst. The 5-hydroxy-1-alkene react with the Co complex …
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Reagents and Strategies for the Total Synthesis of Halogenated Natural Products
… ring expansion, one that transforms tetrahydrofurans into brominated oxocanes (8-membered ring ethers). This BDSB-mediated process is high yielding and both regio- and diastereoselective, making it ideal for application to the synthesis of lauroxocanes: a large family of natural …
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I. Multicatalysis: Development of a BiOTf₃-catalyzed Nucleophilic Addition/Hydrofunctionalization Reaction in the Synthesis of Complex Heterocycles; . . .
… was developed for the synthesis of substituted tetrahydrofurans. This operationally simple method successfully generated complex tetrahyrofurans in moderate to good diastereoselectivity with good functional group tolerance. An analogous hydroamination of non-basic N-tosyl amines was also …
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Untersuchungen zur stereoselektiven Synthese funktionalisierter Tetrahydrofurane durch Vanadium(V)- und Cobalt(II)-katalysierte Oxidationen substituierter Bishomoallylalkohole
Substituierte Tetrahydrofurane sind Bausteine vieler pharmakologisch interessanter Natur- und Wirkstoffe. Deshalb ist die Entwicklung effizienter Methoden zur Darstellung dieser Verbindungsklasse von großer Bedeutung. Bei den Übergansmetall-katalysierten Verfahren erwiesen sich sowohl Vanadium(V)-, …