Video Experimental Relacionado

Updated: Jul 17, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Published on: June 21, 2017

Reacciones de Diels-Alder altamente selectivas de los dienófilos de enyne directamente conectados entre sí

Mingji Dai¹, David Sarlah, Maolin Yu

¹Department of Chemistry, Columbia University, Havemeyer Hall, New York, New York 10027, USA.

Journal of the American Chemical Society

|January 18, 2007

Resumen

Las reacciones de Diels-Alder con los dienófilos de enyne vinculados muestran una alta selectividad. Un grupo activador remoto en el sitio olefínico dicta la regioquímica, lo que permite la síntesis de subestructuras de productos naturales.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química sintética de la química sintética.

Sus antecedentes:

Las reacciones de Diels-Alder son cruciales para formar compuestos cíclicos.
Las Enynes presentan desafíos únicos de reactividad en las cicloadiciones.

Objetivo del estudio:

Para investigar la regioselectividad de las reacciones de Diels-Alder con los dienófilos de enyne vinculados.
Comprender la influencia de los grupos de activación en los resultados de la cicloadición.

Principales métodos:

Reacciones de cicloadición Diels-Alder con dienófilos de enyne sustituidos.
Análisis computacional para explicar la reactividad y la selectividad observadas.

Principales resultados:

Las reacciones de Diels-Alder ocurrieron exclusivamente en el centro acetilenico del enyne.
La regioquímica estaba dominada por un grupo de activación remota en el sitio olefínico, que anulaba al grupo en el acetileno.
Los estudios computacionales racionalizan la preferencia por la cicloadición de acetileno y el control remoto del grupo.

Conclusiones:

Los dienófilos de enyne vinculados ofrecen una alta selectividad en las reacciones de Diels-Alder.
Los grupos de activación remota ejercen un control significativo sobre la regioquímica.
Estos hallazgos abren nuevas rutas sintéticas para productos naturales de tipo orsenilado.

Más Videos Relacionados

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes

Published on: April 1, 2013

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

Published on: August 16, 2018

Videos de Conceptos Relacionados

Diels–Alder Reaction: Characteristics of Dienophiles

Diels–Alder Reaction: Characteristics of Dienophiles

In a Diels–Alder reaction, the diene is usually an electron-rich system and acts as a nucleophile, whereas the dienophile is electron-deficient and functions as an electrophile. Much like the diene, the nature of the dienophile significantly impacts the outcome of the reaction.
Characteristics of Dienophiles
Generally, the best dienophiles are alkenes containing electron-withdrawing substituents such as carbonyl, nitrile, and nitro groups. The feasibility of a Diels–Alder reaction depends on...

Diels–Alder Reaction: Characteristics of Dienes

Diels–Alder Reaction: Characteristics of Dienes

The Diels–Alder reaction brings together a diene and a dienophile to form a six-membered ring. Both components have unique characteristics that influence the rate of the reaction.
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is more stable, the...

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.

Diels–Alder Reaction Forming Cyclic Products: Stereochemistry

Diels–Alder Reaction Forming Cyclic Products: Stereochemistry

The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.

Diels–Alder vs Retro-Diels–Alder Reaction: Thermodynamic Factors

Diels–Alder vs Retro-Diels–Alder Reaction: Thermodynamic Factors

The Diels–Alder reaction is thermally reversible, meaning that the reaction reverts to the starting diene and dienophile under suitable temperatures. The forward reaction gives a cyclohexene derivative and is favored at low to medium temperatures. The reverse process, also called retro-Diels–Alder reaction, is a ring-opening process favored at high temperatures.