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Actividad arilativa enantioselectiva catalizada por níquel del enlace aromático C-O

Jintong Zhang¹, Tingting Sun¹, Zishuo Zhang¹

¹Anhui Agricultural University, Hefei, Anhui 230036, China.

Journal of the American Chemical Society

|October 27, 2021

Resumen

Este estudio presenta la primera activación enantioselectiva de enlaces aromáticos C-O mediante catálisis de níquel. Este método produce eficientemente esqueletos quirales binafílicos valiosos con alto rendimiento y pureza.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

El acoplamiento cruzado catalizado por níquel de electrófilos CO fue establecido por Wenkert en la década de 1970.
La activación asimétrica de enlaces aromáticos C-O mediante catálisis de metales de transición sigue siendo un desafío no reportado.

Objetivo del estudio:

Para lograr la primera activación enantioselectiva de un enlace aromático C-O.
Desarrollar un método catalítico para la síntesis de esqueletos quirales de 2-arilo-2'-hidroxi-1,1'-binaftil (ArOBIN).

Principales métodos:

Acoplamiento cruzado catalítico arilativo de apertura de anillos de diarilfuranos.
Catalización de níquel mediante el uso de ligandos quirales de N-heterocíclicos de carbeno.

Principales resultados:

Se demostró la primera activación enantioselectiva de enlaces aromáticos C-O.
Se han sintetizado con éxito esqueletos quirales de ArOBIN en altos rendimientos con un alto exceso enantiomérico (ee).
Mostró la versatilidad del esqueleto ArOBIN para futuras modificaciones sintéticas.

Conclusiones:

Esta nueva reacción catalizada por níquel proporciona una ruta eficiente a los compuestos de binaftil axialmente quirales.
La metodología desarrollada ofrece condiciones de reacción suaves y una buena economía atómica.
Los esqueletos quirales sintetizados sirven como intermediarios valiosos para crear moléculas complejas, catalizadores y ligandos.

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