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Updated: Dec 29, 2025

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

Arilación de acoplamiento cruzado catalizado por níquel remoto mediante escisión de enlaces C-C habilitada por

Long Huang¹, Tengfei Ji¹, Magnus Rueping^1,2

¹Institute of Organic Chemistry , RWTH Aachen University , Landoltweg 1 , 52074 Aachen , Germany.

Journal of the American Chemical Society

|February 5, 2020

Resumen

Este estudio introduce un nuevo método para crear enlaces carbono-carbono utilizando alcoholes cíclicos y catálisis fotorredóxica con níquel. Este enfoque permite la arilación remota de cetonas, superando los desafíos en la activación directa del enlace C-C.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Las reacciones de acoplamiento cruzado son vitales para la formación de enlaces C-C y C-heteroátomo.
La funcionalización directa del enlace C-H está avanzando, pero la activación del enlace C-C sigue siendo un desafío debido a la inercia del enlace.
Los métodos existentes a menudo requieren socios de acoplamiento preactivados.

Objetivo del estudio:

Desarrollar una estrategia leve y general para la arilación remota y específica del sitio de las cetonas.
Para activar alcoholes cíclicos fácilmente disponibles para desafiar la formación de enlaces C ((sp3) -C ((sp2).
Para utilizar la transferencia multisite concertada de protones y electrones (MS-PCET) mediada por fotorreducción y la catálisis del níquel.

Principales métodos:

Utilizando la transferencia multisite concertada de protones-electrones (MS-PCET) para la generación de radicales alcoxi.
Utilizando la catálisis de níquel para facilitar la reacción de acoplamiento cruzado.
Aprovechando la energía libre de disociación de enlaces (BDFE) como la fuerza motriz termodinámica para la escisión C-C.

Principales resultados:

Activación exitosa de varios alcoholes cíclicos.
Demostración de la arilación remota y específica del sitio de las cetonas.
Formación de enlaces C(sp3) -C(sp2) desafiantes a través de los radicales intermedios.

Conclusiones:

El método desarrollado ofrece un enfoque suave y general para la formación de enlaces C-C.
Esta estrategia supera las limitaciones en la activación directa de bonos C-C.
La combinación de MS-PCET y la catálisis del níquel proporciona una herramienta poderosa para la química sintética.

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