Video Experimental Relacionado

Updated: Mar 19, 2026

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions

Published on: March 20, 2014

Acoplamiento de Kumada asimétrico catalizado por níquel de sulfatos cíclicos simétricos

Meredith S Eno¹, Alexander Lu¹, James P Morken¹

¹Department of Chemistry, Merkert Chemistry Center, Boston College , Chestnut Hill, Massachusetts 02467, United States.

Journal of the American Chemical Society

|June 9, 2016

Resumen

En este estudio se introducen acoplamientos cruzados enantioselectivos catalizados por níquel utilizando sulfatos cíclicos y reactivos de Grignard. El método crea eficientemente moléculas complejas con nuevos centros quirales, avanzando la síntesis asimétrica.

Área de la Ciencia:

Química orgánica
Catálisis asimétrica

Sus antecedentes:

Los sulfatos cíclicos son precursores versátiles en la síntesis orgánica.
El desarrollo de métodos eficientes para crear centros quirales de carbono terciario es crucial en el descubrimiento de fármacos y la ciencia de los materiales.

Objetivo del estudio:

Desarrollar una nueva reacción de acoplamiento cruzado enantioselectiva catalizada por níquel.
Utilizar sulfatos cíclicos simétricos y reactivos aromáticos de Grignard para sintetizar moléculas con centros de carbono terciario asimétricos.

Principales métodos:

Utilizando la catálisis de níquel para las reacciones de acoplamiento cruzado.
Utilizando una gama de sulfatos cíclicos sustituidos y reactivos aromáticos de Grignard.
Realización de estudios mecanicistas para elucidar la vía de reacción.

Principales resultados:

Se han logrado cruces enantioselectivos efectivos entre los sulfatos cíclicos y los reactivos de Grignard.
Se ha demostrado un amplio alcance de sustrato con varios sulfatos cíclicos sustituidos.
Productos generados con éxito que contienen centros de carbono terciario asimétricos.

Conclusiones:

La reacción catalizada por níquel desarrollada proporciona una nueva ruta poderosa para la síntesis asimétrica.
La reacción se produce a través de un mecanismo de adición oxidativa similar al SN2 estereoinvertido.
Esta metodología ofrece un potencial significativo para acceder a moléculas quirales complejas.

Más Videos Relacionados

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Published on: April 4, 2014

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

Preparation and Reactions of Sulfides

Preparation and Reactions of Sulfides

Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.

Aldol Condensation with β-Diesters: Knoevenagel Condensation

Aldol Condensation with β-Diesters: Knoevenagel Condensation

The Knoevenagel condensation is an aldol-type reaction involving the condensation of aldehydes or ketones with active methylene compounds such as β-diesters to produce substituted olefins.

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.

SN2 Reaction: Stereochemistry

S_N2 Reaction: Stereochemistry

In an SN2 reaction, the nucleophilic attack on the substrate and departure of the leaving group occurs simultaneously through a transition state. As the nucleophile approaches the substrate from the back-side, the configuration of the substrate carbon changes from tetrahedral to trigonal bipyramidal and then back to tetrahedral, leading to an inversion in the configuration of the product.
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not...

Vicinal Diols via Reductive Coupling of Aldehydes or Ketones: Pinacol Coupling Overview

Vicinal Diols via Reductive Coupling of Aldehydes or Ketones: Pinacol Coupling Overview

Wilhelm Rudolph Fittig discovered the pinacol coupling reaction in 1859. It is a radical dimerization reaction and involves the reductive coupling of aldehydes or ketones in the presence of hydrocarbon solvent to yield vicinal diols.

Crossed Aldol Reaction Using Strong Bases: Directed Aldol Reaction

Crossed Aldol Reaction Using Strong Bases: Directed Aldol Reaction

The reaction between two different carbonyl compounds comprising α hydrogen in the presence of a strong base like lithium diisopropylamide (LDA) to form a crossed aldol product is known as a directed aldol reaction. The directed aldol reaction is depicted in Figure 1.