Cyclopropanation
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. Estudo da Aplicação de Brometo de Índio(I) em Reações para Formação de Ligações Carbono-Carbono / Studies on the Application of Indium(I) Bromide in Carbon-Carbon
This PhD thesis describes our results on the application of indium(I) bromide in carbon-carbon bond forming reactions. Indium enolates, generated in situ from the reaction between indium(I) bromide and α,α-dichloroketones, react with carbonyl compounds and electron-deficient alkenes. Reactions of indium enolate with α,α-dichloroketones, i
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/03/2011
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2. Catálise assimétrica na ciclopropanação de olefinas
The main methodologies in the asymmetric cyclopropanation of alkenes with emphasis on asymmetric catalysis are covered. Exemples are the Simmons-Smith reaction, the use of diazoalkanes and reactions carried out by decomposition of alpha-diazoesters in the presence of transition metals.
Química Nova. Publicado em: 2007
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3. C60-based ebselen derivative: synthesis by bingel cyclopropanation and enhanced antioxidative and neuroprotective activity
Um derivado de ebselen baseado em C60, 3, foi sintetizado pela reação de ciclopropanação de Bingel envolvendo C60 e manolato de ebselen, 2. O produto foi sintetizado em três etapas, partindo de cloreto de 2-cloro-selenobenzoila e 2-(2-aminoetoxietanol), com rendimento de 42% (baseado no consumo de C60). O composto 3 foi caracterizado estruturalmente por
Journal of the Brazilian Chemical Society. Publicado em: 2007
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4. Estudo da reação de Simmons-Smith : obtenção de metilenociclopropanos substituidos, de interesse industrial
The Simmons-Smith reaction is a very useful synthetic route to obtain substituted cyclopropanes from the corresponding olefins and a carbene source. Since there is no agreement in the literature with respect to the best procedure for this reaction, some parameters that influence its yield were studied. To obtain bicyclo[4,1,0]heptane (norcarane) from cyclohe
Publicado em: 1995
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5. Cicloprogramação de 1,3-dienos substituidos pela reação de Simmons-Smith
The cyclopropanation of 1,3-diene by the Simmons-Smith reaction is normally inefficient and generates very low yields in products. The objective of this work was to verify the reactivity, site-selectivity, and stereospecificity of cyclopropanation of substituted 1,3-dienes, under drastic conditions of pressure (up to 4 kbar) and temperature (from 80 to 120°
Publicado em: 1993
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6. Estudo da reação de Simmons-Smith : obtenção vinilciclopropanos substituidos de interesse industrial
Of the procedures described in the literature, that of Rawson e Harrison gives under standard conditions the best results for the cyclopropanation of cyclohexene. We found that the noble metal salt used to activate the metallic zinc has a more important role than to clean its surface, as the yield of the reaction is strongly influenced by the anion. In the p
Publicado em: 1990
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7. Catalytic asymmetric reactions for organic synthesis: The combined C—H activation/Cope rearrangement
The development of new catalytic asymmetric reactions can lead to exciting new strategies for organic synthesis. This article describes the synthetic utility of the combined C—H activation/Cope rearrangement, achieved by dirhodium tetraprolinate-catalyzed reaction of vinyldiazoacetates with compounds containing allylic C—H bonds. The transformation is hi
National Academy of Sciences.
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8. A shotgun lipidomics approach in Sinorhizobium meliloti as a tool in functional genomics
A shotgun lipidomics approach that allowed the analysis of eight lipid classes directly from crude extracts of the soil bacterium Sinorhizobium meliloti is presented. New MS-MS transitions are reported for the analysis of monomethylphosphatidylethanolamines, dimethylphosphatidylethanolamines, and three bacterial non-phosphorus-containing lipid classes [sulfo
American Society for Biochemistry and Molecular Biology.
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9. Identification of a gene involved in the biosynthesis of cyclopropanated mycolic acids in Mycobacterium tuberculosis.
Mycolic acids represent a major constituent of the mycobacterial cell wall complex, which provides the first line of defense against potentially lethal environmental conditions. Slow-growing pathogenic mycobacteria such as Mycobacterium tuberculosis modify their mycolic acids by cyclopropanation, whereas fast-growing saprophytic species such as Mycobacterium
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10. Chrysanthemyl diphosphate synthase: Isolation of the gene and characterization of the recombinant non-head-to-tail monoterpene synthase from Chrysanthemum cinerariaefolium
Chrysanthemyl diphosphate synthase (CPPase) catalyzes the condensation of two molecules of dimethylallyl diphosphate to produce chrysanthemyl diphosphate (CPP), a monoterpene with a non-head-to-tail or irregular c1′-2-3 linkage between isoprenoid units. Irregular monoterpenes are common in Chrysanthemum cinerariaefolium and related members of the Aste
The National Academy of Sciences.