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Cu (II) -Cu (I) cooperación sinérgica para liderar la activación de la alquina C-H

Ruopeng Bai¹, Guanghui Zhang, Hong Yi

¹College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, P.R. China.

Journal of the American Chemical Society

|November 11, 2014

Resumen

La catálisis del cobre permite una activación eficiente de la alquina C-H y el homoacoplamiento. El cobre (I) es clave en el paso lento de activación de C-H, mientras que el cobre (II) se oxida en la rápida formación de enlaces C-C.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis es la catálisis.
La espectroscopia es una técnica de espectroscopia.

Sus antecedentes:

La activación de la alquina C-H y el homoacoplamiento son transformaciones sintéticas cruciales.
Comprender el ciclo catalítico de las reacciones mediadas por el cobre es esencial para la optimización.

Objetivo del estudio:

Para investigar el mecanismo de una activación eficiente de alquino C-H y el procedimiento de homoacoplamiento.
Para aclarar los roles de los diferentes estados de oxidación del cobre (Cu(II) / Cu(I)) en el proceso catalítico.

Principales métodos:

Espectroscopia Raman in situ para estudios cinéticos.
Infrarrojo (IR), Resonancia Paramagnética Electrónica (EPR) y espectroscopia de absorción de rayos X para el análisis estructural.
Análisis cinético para determinar las etapas que determinan la velocidad.

Principales resultados:

El cobre (Cu) se identifica como la especie activa en el paso de activación C-H que determina la velocidad.
El cobre (Cu) actúa como un oxidante en la etapa rápida de formación de enlaces C-C.
La evidencia espectroscópica indica una interacción más fuerte de Cu (I) con alquina durante la activación de C-H.

Conclusiones:

Se propone un mecanismo sinérgico que involucra tanto a Cu (I) como a Cu (II) para la activación de la alquina C-H y la reacción de homoacoplamiento.
El entorno de coordinación de las especies de cobre está influenciado por la interacción entre Cu (I) y Cu (II).
Este estudio proporciona una visión mecanicista detallada de las transformaciones de alquinos catalizados por el cobre.

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