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Ru (II) - Aminación catalizada de los fluoruros de arilo a través de la coordinación

Qi-Kai Kang^1,2, Yunzhi Lin^1,2, Yuntong Li^1,2

¹Institute of Natural Sciences , Westlake Institute for Advanced Study , 18 Shilongshan Road , Hangzhou 310024 , Zhejiang , China.

Journal of the American Chemical Society

|February 11, 2020

Resumen

Este estudio introduce una nueva reacción de sustitución aromática nucleofílica catalizada por rutenio (S_NAr) utilizando fluoruros de arilo. El ligando hemilabil desarrollado facilita la aminación eficiente de arenas neutras y ricas en electrones, simplificando las rutas sintéticas.

Área de la Ciencia:

Química organometálica
Catálisis
Síntesis orgánica

Sus antecedentes:

Las reacciones de sustitución aromática nucleófila (S_NAr) son fundamentales en la síntesis orgánica.
Los fluoruros de arilo a menudo son sustratos difíciles para el S_NAr debido a su fuerte enlace carbono-fluoro.
El desarrollo de sistemas catalíticos eficientes para el S_NAr de los fluoruros de arilo sigue siendo un área activa de investigación.

Objetivo del estudio:

Desarrollar una nueva reacción S_NAr catalizada por rutenio (Ru) para los fluoruros de arilo.
Investigar el papel de los ligandos hemilabiles en la mejora de la actividad catalítica.
Para permitir la aminación de arenas neutras y ricas en electrones sin requerir un exceso de sustrato.

Principales métodos:

Desarrollo de la reacción catalizada por rutenio.
Utilizando ligandos hemilabiles para modificar las propiedades del catalizador.
El uso de fluoruros de arilo como reactivos limitantes.
Estudios mecanicistas que involucran la formación del complejo η.

Principales resultados:

Se logró una exitosa arminación S_N de fluoruros de arilo utilizando un catalizador de ligando Ru/hemilabil.
Se observó una mejora significativa del ligando, lo que permite la reacción con arenas ricas en electrones y neutras.
La reacción procedió eficientemente sin necesidad de un exceso de sustratos de areno.
Los estudios mecánicos indicaron la formación de un complejo de Ru-areno η6 y la disociación del producto facilitada por el ligando hemilabil.

Conclusiones:

Se ha desarrollado un nuevo y eficiente sistema catalítico Ru/hemilabile-ligando para S_NAr de fluoruros de arilo.
Los ligandos hemilabílicos juegan un papel crucial en la promoción del ciclo catalítico al facilitar la liberación del producto.
Esta metodología ofrece un enfoque simplificado para la síntesis de arenas aminadas a partir de fluoruros de arilo.

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