Video Experimental Relacionado

Updated: Oct 27, 2025

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

Dirhodium ((II) / Xantphos-Catalyzed Relay Carbene Insertion y Proceso de Alquilación Alilica: Desarrollo de la

Bin Lu¹, Xinyi Liang², Jinyu Zhang¹

¹State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

Journal of the American Chemical Society

|July 23, 2021

Resumen

Este estudio introduce una nueva reacción de tres componentes catalizada por dirodio (II) / xantfos para sintetizar derivados complejos de ácido α-cuaternario. El método incorpora de manera eficiente las fracciones alilicas, superando un desafío significativo en la síntesis orgánica.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Las reacciones multicomponentes catalizadas por dirodio son herramientas avanzadas en la síntesis orgánica.
La introducción de fracciones alilicas a través de metales intermedios alilicos en estas reacciones es un desafío.

Objetivo del estudio:

Desarrollar una reacción eficiente de tres componentes para sintetizar derivados α-cuaternarios de α-aminoácidos.
Para superar el desafío de incorporar porciones alilicas en reacciones catalizadas por dirodio.

Principales métodos:

Utilizando un nuevo sistema catalítico de dirodio (II) / xantfos.
Utilizando aminas fácilmente accesibles, compuestos diazo y compuestos alilicos como materiales de partida.
Realización de estudios mecanicistas para elucidar la vía de reacción.

Principales resultados:

Síntesis exitosa de diversos derivados del ácido α-cuaternario.
Logrado buenos rendimientos con alto átomo y economía de paso.
Se ha demostrado un proceso de inserción de carbenos catalizado por dirodio (II) y alquilación de alelo.

Conclusiones:

La nueva catálisis de dirodio (II) / xantfos permite una síntesis eficiente de derivados de aminoácidos complejos.
El ligando de Xantphos modifica las propiedades catalíticas del dirodio para una alquilación alilica efectiva.
Este método ofrece una estrategia valiosa para construir moléculas arquitectónicamente complejas.

Más Videos Relacionados

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis

Published on: February 16, 2020

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Published on: January 3, 2018

Videos de Conceptos Relacionados

Electrophilic 1,2- and 1,4-Addition of X2 to 1,3-Butadiene

Electrophilic 1,2- and 1,4-Addition of X₂ to 1,3-Butadiene

Electrophilic addition of halogens to alkenes proceeds via a cyclic halonium ion to form a 1,2-dihalide or a vicinal dihalide.

Radical Anti-Markovnikov Addition to Alkenes: Overview

Radical Anti-Markovnikov Addition to Alkenes: Overview

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

Cycloaddition Reactions: Overview

Cycloaddition Reactions: Overview

Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.

Radical Substitution: Allylic Bromination

Radical Substitution: Allylic Bromination

In organic synthesis, the formation of products can be altered by changing the reaction conditions. For example, a dibromo addition product is formed when propene is treated with bromine at room temperature. In contrast, propene undergoes allylic substitution in non-polar solvents at high temperatures to give 3-bromopropene. In order to avoid the addition reaction, the bromine concentration must be kept as low as possible throughout the reaction. This can be achieved using N-bromosuccinimide...

[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.

Electrophilic Addition to Alkynes: Halogenation

Electrophilic Addition to Alkynes: Halogenation

Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.