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Nitrato meta-selectivo de CAr-H de los arenos a través de una estrategia de orto-metalización catalizada de Ru3 ((CO)

Zhoulong Fan^1,2, Jiabin Ni^1,2, Ao Zhang^1,2

¹CAS Key Laboratory of Receptor Research, and Synthetic Organic & Medicinal Chemistry Laboratory (SOMCL), Shanghai Institute of Materia Medica (SIMM), Chinese Academy of Sciences , Shanghai 201203, China.

Journal of the American Chemical Society

|May 17, 2016

Resumen

Los investigadores desarrollaron un nuevo método catalizado por rutenio para la nitratación meta-selectiva de CAr-H de arenas. Este enfoque eficiente utiliza materiales fácilmente disponibles y ofrece una vía rápida para sintetizar compuestos farmacéuticos.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La funcionalidad directa C-H ofrece rutas sintéticas de economía atómica.
El logro de la meta-selectividad en la funcionalización C-H sigue siendo un desafío significativo.
Los métodos existentes a menudo carecen de eficiencia o de amplia aplicabilidad.

Objetivo del estudio:

Informar sobre la primera nitratación meta-selectiva de arenas catalizadas por metales de transición.
Desarrollar un método eficiente y versátil para introducir nitrogrupos en la meta posición.
Proporcionar una síntesis simplificada de valiosos productos farmacéuticos intermedios.

Principales métodos:

El grupo de carbonilo de rutenio (Ru3 (CO) 12) catalizado por la nitratación de CAr-H.
El trihidrato de nitrato de cobre (Cu (NO3) 2·3H2O) como fuente de nitro.
Se utilizan N-heterociclos o grupos de dirección de oximidos para la meta-selectividad.

Principales resultados:

Se ha logrado una meta-selectividad exclusiva en la nitratación de diversas arenas.
Se identificó un intermediario clave de rutenio metalizado orto-CAr-H (18e especies octaédricas).
Demostró la utilidad del método para sintetizar moléculas farmacéuticas.

Conclusiones:

Se estableció una nueva y eficiente estrategia de nitratación meta-selectiva de CAr-H.
El método desarrollado permite la síntesis atómica y económica.
Este enfoque acelera el descubrimiento y la producción de importantes compuestos bioactivos.

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