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

Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration02:34

Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration

9.9K
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.
9.9K
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation02:17

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

4.0K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
4.0K
Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule02:17

Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule

18.1K
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...
18.1K
Regioselectivity and Stereochemistry of Hydroboration02:36

Regioselectivity and Stereochemistry of Hydroboration

9.6K
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
9.6K
Acid-Catalyzed α-Halogenation of Aldehydes and Ketones01:21

Acid-Catalyzed α-Halogenation of Aldehydes and Ketones

5.1K
By replacing an α-hydrogen with a halogen, acid-catalyzed α-halogenation of aldehydes or ketones yields a monohalogenated product
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
5.1K
Radical Anti-Markovnikov Addition to Alkenes: Overview01:25

Radical Anti-Markovnikov Addition to Alkenes: Overview

4.3K
The addition of hydrogen bromide to alkenes in the presence of hydroperoxides or peroxides proceeds via an anti-Markovnikov pathway and yields alkyl bromides.
4.3K

También podría leer

Artículos Relacionados

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

Ordenar por
Same author

Self-supported catalysts.

Chemical reviews·2008
Same author

[The local control of radiotherapy following Ivor-Lewis esophagectomy in the patients with stage II A middle-third thoracic esophageal cancer].

Zhonghua wai ke za zhi [Chinese journal of surgery]·2008
Same author

Magnetic loading of carbon nanotube/nano-Fe(3)O(4) composite for electrochemical sensing.

Talanta·2008
Same author

Carbon nanotube/polystyrene composite electrode for microchip electrophoretic determination of rutin and quercetin in Flos Sophorae Immaturus.

Talanta·2008
Same author

[Observation on efficacy of large volume whole lung lavage in treatment of pneumoconiosis].

Zhonghua lao dong wei sheng zhi ye bing za zhi = Zhonghua laodong weisheng zhiyebing zazhi = Chinese journal of industrial hygiene and occupational diseases·2008
Same author

[Application of large volume whole lung lavage in pneumoconiosis].

Zhonghua lao dong wei sheng zhi ye bing za zhi = Zhonghua laodong weisheng zhiyebing zazhi = Chinese journal of industrial hygiene and occupational diseases·2008

Video Experimental Relacionado

Updated: Mar 14, 2026

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
10:10

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Published on: July 28, 2018

6.9K

Activación del enantioselectivo del metileno C ((sp3) -H acelerado por ligando

Gang Chen1, Wei Gong1, Zhe Zhuang1

  • 1The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.

Science (New York, N.Y.)
|October 5, 2016
PubMed
Resumen

Los investigadores desarrollaron ligandos quirales para la inserción asimétrica de paladio en enlaces carbono-hidrógeno (C-H). Este avance permite la funcionalización enantioselectiva de enlaces C-H en amidas y ácidos carboxílicos, avanzando la catálisis asimétrica.

Más Videos Relacionados

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
08:25

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs

Published on: January 17, 2020

7.9K
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

10.0K

Videos de Experimentos Relacionados

Last Updated: Mar 14, 2026

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
10:10

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Published on: July 28, 2018

6.9K
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
08:25

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs

Published on: January 17, 2020

7.9K
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

10.0K

Área de la Ciencia:

  • Química orgánica
  • Catálisis
  • Síntesis asimétrica

Sus antecedentes:

  • La diferenciación de enlaces procirales carbono-hidrógeno (C-H) en un solo carbono de metileno a través de la inserción asimétrica de metales es un desafío significativo en la química sintética.
  • Los métodos existentes a menudo luchan con la selectividad y la eficiencia, lo que limita el alcance de la funcionalización C-H.

Objetivo del estudio:

  • Desarrollar nuevos ligandos quirales para la inserción asimétrica de paladio en enlaces C-H procirales.
  • Para lograr la funcionalización enantioselectiva de los enlaces β-metileno C-H en amidas alifáticas y ácidos carboxílicos.

Principales métodos:

  • Descubrimiento de ligandos de aminoetilquinolina quirales protegidos por acetil.
  • Aplicación de complejos de paladio con estos ligandos para la activación catalítica de C-H.
  • Utilizando ligandos bidentados para acelerar la activación de C-H y superar las reacciones de fondo.

Principales resultados:

  • Inserción asimétrica exitosa de paladio en enlaces procirales C-H en un único centro de carbono de metileno.
  • Se logró la funcionalización enantioselectiva de los enlaces β-metileno C-H en amidas alifáticas.
  • Se ha demostrado una arilación enantioselectiva β-C-H de ácidos carboxílicos simples sin grupos direccionales.

Conclusiones:

  • Los ligandos de aminoetilquinolina protegidos por acetilo quiral permiten efectivamente la inserción asimétrica de paladio en los enlaces C-H procirales.
  • La aceleración del ligando es crucial para lograr una alta enantioselectividad en la activación de C-H, particularmente para sustratos desafiantes.
  • Esta metodología amplía el alcance de la funcionalización C-H enantioselectiva para las amidas y los ácidos carboxílicos.