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Lograr el acoplamiento reductor catalizado por níquel C (sp2) -B de bromoboranos a través de la inversión de la

Chun-Fu Meng¹, Bei-Bei Zhang¹, Qiang Liu¹

¹School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.

Journal of the American Chemical Society

|March 4, 2024

Resumen

Los investigadores desarrollaron una nueva reacción de acoplamiento cruzado reductor catalizada por níquel para formar enlaces de carbono y boro. Este método sintetiza eficientemente los ésteres de boronato de arilo a partir de haluros de arilo y bromoboranos, minimizando los subproductos.

Área de la Ciencia:

Química orgánica
Catálisis
Química del organoboron

Sus antecedentes:

Los acoplamientos cruzados catalizados por metales de transición son vitales para la formación de enlaces C-C y C-Si.
Los acoplamientos cruzados reductivos para la construcción de enlaces C ((sp2) -B siguen siendo poco explorados.
Los ésteres de boronato de arilo son valiosos intermediarios sintéticos.

Objetivo del estudio:

Desarrollar un nuevo acoplamiento reductivo catalizado por níquel para la formación de enlaces C ((sp2) -B.
Para establecer una síntesis conveniente de ésteres de boronato de arilo.
Investigar el mecanismo de reacción y optimizar las condiciones.

Principales métodos:

Reacción de acoplamiento cruzado reductor catalizado por níquel entre haluros de arilo y bromoboranos.
Utilizó una base de Lewis (2-MeO-py) para activar los bromoboranos.
Estudios mecánicos que incluyen la activación del catalizador y la secuencia de adición del sustrato.

Principales resultados:

Construido con éxito el enlace C ((sp2) -B a través de acoplamiento cruzado reductivo.
Sintetizó una amplia gama de ésteres de boronato de arilo utilizando materiales de partida fácilmente disponibles.
Se ha demostrado que se minimizan los subproductos del homoacoplamiento sin una carga excesiva del sustrato.

Conclusiones:

Se ha establecido un nuevo y eficiente protocolo catalizado por níquel para la síntesis del éster de boronato de arilo.
La activación de la base de Lewis de los bromoboranos es crucial para el éxito de la reacción.
Este método ofrece una alternativa valiosa para la síntesis de compuestos de organoboron.

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