Video Experimental Relacionado

Updated: Jun 13, 2025

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 asimétrico migratorio Nozaki-Hiyama-Kishi catalizado por cobalto

Jian Chen¹, Lifu Wu¹, Zhiyong Song¹

¹State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.

Journal of the American Chemical Society

|September 16, 2024

Resumen

Este estudio introduce un nuevo acoplamiento asimétrico migratorio Nozaki-Hiyama-Kishi catalizado por cobalto. Este método sintetiza eficientemente moléculas complejas a partir de precursores simples utilizando la funcionalización de enlaces C-H.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis sostenible

Sus antecedentes:

La funcionalización selectiva del enlace C-H es clave para una síntesis eficiente.
La migración de n metales ofrece un enfoque sostenible para moléculas complejas.
La catálisis asimétrica es vital para producir compuestos enantioméricamente puros.

Objetivo del estudio:

Desarrollar un nuevo acoplamiento migratorio asimétrico co-catalizado Nozaki-Hiyama-Kishi (NHK).
Para lograr la funcionalización selectiva de los enlaces C-H a través de un desplazamiento único cobalto/hidruro.
Para controlar la regio-, E/Z- y la enantioselectividad en las reacciones de acoplamiento NHK.

Principales métodos:

Acoplamiento NHK migratorio asimétrico catalizado por cobalto.
Utilizando arilo (pseudo) haluros y aldehídos como electrófilos.
Utilizando una estrategia catalítica de relevo de ligando para el acoplamiento arilo-arilo.

Principales resultados:

Se logró un desplazamiento sin precedentes de arilo a alquenilo 1,4-cobalto/hidruro.
Se demostró un control exquisito de la regio-, E/ Z- y enantioselectividad a través de la elección del ligando.
El método se extendió al acoplamiento NHK migratorio asimétrico arilo-arilo.

Conclusiones:

Este trabajo presenta una plataforma versátil para sintetizar valiosos adductos de NHK.
La metodología desarrollada permite el acceso a los alcoholes quirales y bencílicos.
Estos productos sirven como versátiles sintetizadores para futuras transformaciones químicas.

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

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

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

Published on: November 9, 2019

Videos de Conceptos Relacionados

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

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...

[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement

[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement

The Cope rearrangement is classified as a [3,3] sigmatropic shift in 1,5-dienes, leading to a more stable, isomeric 1,5-diene. The reaction involves a concerted movement of six electrons, four from two π bonds and two from a σ bond, via an energetically favorable chair-like transition state.

[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.

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.

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.

Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.