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Acoplamiento electrófilo de cloruros de alquilo no activados

Holt A Sakai¹, Wei Liu¹, Chi Chip Le¹

¹Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States.

Journal of the American Chemical Society

|June 23, 2020

Resumen

Este estudio introduce un nuevo reactivo organosilano para la activación de cloruros de alquilo no reactivos. Esto permite el primer acoplamiento electrófilo cruzado de cloruros de alquilo y arilo utilizando la catálisis doble níquel/fotorredóxido.

Área de la Ciencia:

Química orgánica
Catálisis
La fotoquímica

Sus antecedentes:

Los cloruros de alquilo son electrófilos subutilizados en la catálisis de metales de transición debido a los desafíos en la activación del enlace C ((sp3) -Cl.
El desarrollo de métodos eficientes para activar estos enlaces es crucial para expandir las capacidades sintéticas.

Objetivo del estudio:

Desarrollar un nuevo método para activar los cloruros de alquilo.
Para permitir el acoplamiento electrófilo de cloruros de alquilo no activados con cloruros de arilo.

Principales métodos:

Desarrollo de un nuevo reactivo organosilano para la abstracción de átomos de cloro.
Utilizando un protocolo catalítico de doble níquel y fotorreducción.
El uso de condiciones fotocatalíticas suaves.

Principales resultados:

Demostración exitosa de la abstracción de átomos de cloro de los cloruros de alquilo utilizando el reactivo organosilano.
El primer acoplamiento electrofilo cruzado de cloruros de alquilo y cloruros de arilo no activados.
Síntesis de diversos productos acoplados C ((sp2) - C ((sp3)), incluidos los análogos de fármacos.

Conclusiones:

La metodología desarrollada supera las limitaciones en la activación del enlace C ((sp3) -Cl.
Este enfoque proporciona acceso a valiosas moléculas funcionalizadas de los bloques de construcción de cloruro orgánico abundantes.
El método tiene aplicaciones potenciales en el descubrimiento y síntesis de fármacos.

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