Jove
Visualize
Contáctanos
JoVE
x logofacebook logolinkedin logoyoutube logo
ACERCA DE JoVE
Visión GeneralLiderazgoBlogCentro de Ayuda JoVE
AUTORES
Proceso de PublicaciónConsejo EditorialAlcance y PolíticasRevisión por ParesPreguntas FrecuentesEnviar
BIBLIOTECARIOS
TestimoniosSuscripcionesAccesoRecursosConsejo Asesor de BibliotecasPreguntas Frecuentes
INVESTIGACIÓN
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchivo
EDUCACIÓN
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualCentro de Recursos para ProfesoresSitio de Profesores
Términos y Condiciones de Uso
Política de Privacidad
Políticas

Videos de Conceptos Relacionados

Isomerism in Alkenes02:01

Isomerism in Alkenes

Alkenes like 1-butene and 2-butene exhibit constitutional isomerism, as they differ in the position of the double bond. Further, 2-butene exhibits stereoisomerism and exists as two distinct compounds differing in spatial arrangement.
An isomer is called cis-2-butene when the methyl groups are on the same side of the double bond, and the other stereoisomer, in which methyl groups are on the opposite side of the double bond, is called trans-2-butene. The cis and trans stereoisomers are not...
Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule02:17

Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule

If a set of reactants can yield multiple constitutional isomers, but one of the isomers is obtained as the major product, the reaction is said to be regioselective. In such reactions, bond formation or breaking is favored at one reaction site over others.
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
E1 Reaction: Stereochemistry and Regiochemistry02:43

E1 Reaction: Stereochemistry and Regiochemistry

One of the critical aspects of the E1 reaction mechanism, as also observed in E2, is the regiochemistry, with multiple regioisomers obtained as products. In the example discussed, the presence of water as a weak base favors elimination over substitution to generate two alkenes. Given that alkenes’ stability increases with the number of alkyl groups across the double bond, typically, E1 reactions lead to the Zaitsev product, for this is more substituted and stable than the Hofmann product.
E2 Reaction: Stereochemistry and Regiochemistry02:43

E2 Reaction: Stereochemistry and Regiochemistry

Elimination reactions of alkyl halides can yield one or more alkenes depending on the specific regiochemical and stereochemical considerations. While the regiochemistry of the reaction governs the location of the double bond in the product, the stereochemical requirements often influence the geometry.
When a substrate with two different β hydrogens undergoes an E2 elimination, the presence of a strong base can yield two regioisomeric alkenes. The more-substituted alkene is the major product and...
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration02:34

Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration

The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
Regioselectivity of Electrophilic Additions-Peroxide Effect02:35

Regioselectivity of Electrophilic Additions-Peroxide Effect

In the presence of organic peroxides, the addition of hydrogen bromide to an alkene yields the isomer that is not predicted by Markovnikov’s rule. For example, the addition of hydrogen bromide to 2-methylpropene in the presence of peroxides gives 1-bromo-2-methylpropane. This addition reaction proceeds via a free radical mechanism, which reverses the regioselectivity. The free radical reaction mechanism involves three stages: initiation, propagation, and termination.

También podría leer

Artículos Relacionados

Artículos vinculados a este trabajo por autores compartidos, revista y gráfico de citas.

Ordenar por
Same author

A Methodology for the Analysis of Water Oxidation Electrocatalysts in the Absence of Limiting Current that Avoids the Pitfalls of Existing Methods.

ChemSusChem·2025
Same author

Electron-Donating <i>para</i>-Substituent (X) Enhances the Water Oxidation Activity of the Catalyst Ru(4'-X-terpyridine)(phenanthroline-SO<sub>3</sub>)<sup></sup>.

Inorganic chemistry·2025
Same author

Ruthenium complexes with triazenide ligands bearing an N-heterocyclic moiety, and their catalytic properties in the reduction of nitroarenes.

RSC advances·2024
Same author

(CAAC)Copper Catalysis Enables Regioselective Three-Component Carboboration of Terminal Alkynes.

ACS catalysis·2023
Same author

Stable Singlet Carbenes as Organic Superbases.

Angewandte Chemie (International ed. in English)·2021
Same author

Cyclic (Alkyl)(amino)carbene Ligands Enable Cu-Catalyzed Markovnikov Protoboration and Protosilylation of Terminal Alkynes: A Versatile Portal to Functionalized Alkenes*.

Angewandte Chemie (International ed. in English)·2021

Video Experimental Relacionado

Updated: May 21, 2026

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators
06:31

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

Published on: November 27, 2015

Isomerización estereoselectiva de alquenos en una posición.

Casey R Larsen1, Douglas B Grotjahn

  • 1Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182-1030, USA.

Journal of the American Chemical Society
|June 19, 2012
PubMed
Resumen
Este resumen es generado por máquina.

Este estudio introduce el catalizador 1, una solución altamente eficiente para la isomerización selectiva de alquenos. Produce rápidamente más de 99,5% de productos de E-alqueno con una excepcional selectividad cinética, incluso para sustratos sensibles.

Más Videos Relacionados

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
07:36

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Published on: November 9, 2019

Videos de Experimentos Relacionados

Last Updated: May 21, 2026

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators
06:31

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

Published on: November 27, 2015

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
07:36

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Published on: November 9, 2019

Área de la Ciencia:

  • Química orgánica es la química orgánica.
  • La catálisis por catálisis.
  • Síntesis estereoselectiva por síntesis.

Sus antecedentes:

  • La isomerización de alqueno presenta desafíos en el control de la posición del enlace doble y la selectividad E:Z.
  • El desarrollo de catalizadores eficientes para transformaciones selectivas es crucial en la síntesis orgánica.

Objetivo del estudio:

  • Introducir y evaluar el catalizador 1 para la monoisomerización selectiva de alquenos multifuncionales.
  • Para demostrar la alta eficiencia y selectividad del catalizador 1 en condiciones suaves.

Principales métodos:

  • Utilizado catalizador 1 para la isomerización de varios alquenos multifuncionales.
  • Reacciones realizadas a temperatura ambiente con bajas cargas de catalizador (0,01-0,1 mol%).
  • Se analizó la cinética de la reacción y la selectividad del producto utilizando técnicas analíticas.

Principales resultados:

  • Se ha logrado una selectividad >99.5% del producto E en la isomerización de alquenos.
  • Se ha demostrado que la reacción se completa rápidamente (en menos de 10 minutos) a temperatura ambiente.
  • Demostró la capacidad del catalizador 1 para generar enolos y enamidas sensibles.
  • Se observó una selectividad cinética extremadamente alta, con una isomerización de E a Z de <10(-6) veces la tasa de formación.

Conclusiones:

  • El catalizador 1 es un catalizador altamente eficiente y selectivo para la isomerización de alquenos.
  • El catalizador permite la síntesis de valiosos productos de E-alqueno en condiciones suaves y rápidas.
  • El catalizador 1 ofrece ventajas significativas para la síntesis de moléculas complejas con grupos funcionales sensibles.