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Showing 1 to 13 of 13 for “"cycloisomerization"”.
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Transition-metal catalysis of cyclocarbonylation and cycloisomerization reactions
… of an early transition-metal-catalyzed enyne cycloisomerization is described. Titanocene dicarbonyl was shown to catalyze the cycloisomerization of enynes and dienynes to 1,4-dienes and allylic allenes, respectively. Examination of the scope of the reaction demonstrates that only …
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Direct synthesis of pyridine and pyrimidine derivatives
… Pyridine Derivatives via the Ruthenium-Catalyzed Cycloisomerization of 3-Azadienynes. The two-step conversion of various N-vinyl and N-aryl amides to the corresponding substituted pyridines and quinolines, respectively, is described. The process involves the direct conversion of amides, including …
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Mechanistic Studies of pi-Activation Catalysis by Cationic Gold(I) and Brønsted-acid
… or heteroatom-nucleophiles across π-bonds or cycloisomerizations of enynes and related π-systems. Mechanisms involving outer-sphere attack of a nucleophile on the electrophilic π-ligand of a cationic gold π-complex are typically invoked for gold(I)-catalyzed hydrofunctionalization and …
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Rhodium-Catalyzed Enantioselective Desymmetrizations of Oxabicyclic Alkenes and Alkene Difunctionalization via Nickel-Catalyzed Arylcyanation
… and development of a novel enantioselective cycloisomerization reaction of oxabicyclic alkenes. Our work on developing the intramolecular asymmetric ring opening reaction led to the discovery of a novel epoxide synthesis. Specifically, when bridgehead substituted oxabicyclic alkenes with …
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Total Synthesis of the Unique Pederin Family Member Psymberin & Chemical Studies Toward Saliniketal Family Members: Saliniketal a, Salinisporamycin and Rifsaliniketal
… and a stepwise Sonogashira coupling/cycloisomerization/reduction sequence to construct the dihydroisocoumarin unit. The total synthesis of psymberin and its analogs would provide sufficient material for mode-of-action and SAR studies. The fourth chapter describes the biological …
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Ruthenium-Catalyzed Transformations for the Synthesis of Conjugated Dienes
… scaffolds is described. </p> <p> Lastly, the cycloisomerization of silicon-tethered 1,7-enynes to form 1,3-dienes utilizing catalytic Cp*Ru(COD)Cl is described herein. The reaction optimization, mechanistic hypothesis, substrate tolerance and synthetic utility is discussed. The question of …
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Total synthesis of oxaphenalenone natural products
… the syntheses of congeners B–E using a powerful cycloisomerization/cycloaddition strategy will be presented along with efforts to construct the spiroketal congener neonectrolide A. We will also discuss our synthetic efforts towards dimeric members of this natural product family. Namely, …
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Mining the enolase superfamily for new functions: investigations of D-glucarate dehydratase related proteins (GlucDRP) and L-lyxonate dehydratase proteins (LyxD)
… epimerization, deamination, racemization or cycloisomerization. There have been enough studies of this superfamily to provide valuable insight into the types of reactions performed based on catalytic residues and substrate specificity residues, establishing basis for functional …
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Functional assignments in the enolase superfamily: investigations of two divergent groups of D-galacturonate dehydratases and galactarate dehydratase-III
… epimerization, deamination, racemization or cycloisomerization. There have been enough studies of this superfamily to provide valuable insight into the types of reactions performed based on catalytic residues and substrate specificity residues, laying the groundwork for functional …
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Síntesis de compuestos orgánicos de azufre mediante el empleo de catalizadores metálicos, reactivos electrófilos y ácidos de brønsted
Uno de los principales retos de la Química Orgánica es el diseño de nuevos métodos de síntesis para la obtención de moléculas orgánicas habitualmente difíciles de acceder por otras vías. En este sentido, nuestro grupo de investigación se centra en el estudio de nuevos métodos de Síntesis Orgánica, …
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Reacciones de cicloisomerización y alcoxiciclación de o-(Alquinil)estirenos y de 1,3-Dien-5-inos catalizadas por complejos de oro(I)
La catálisis homogénea con complejos de oro ha sufrido un desarrollo espectacular en los últimos años convirtiéndose en una herramienta muy útil para la síntesis de una gran variedad de estructuras complejas, que no son accesibles mediante metodologías convencionales. Esta tesis se ha centrado en …