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Complejos organometálicos de níquel (III) relevantes para el acoplamiento cruzado y las reacciones de formación de

Bo Zheng¹, Fengzhi Tang, Jia Luo

¹Department of Chemistry, Washington University , One Brookings Drive, St. Louis, Missouri 63130-4899, United States.

Journal of the American Chemical Society

|April 10, 2014

Resumen

Este estudio informa sobre el aislamiento y la caracterización de los complejos de níquel (III), demostrando su actividad catalítica en reacciones cruciales de formación de enlaces C-C y C-heteroatomo, incluido el acoplamiento cruzado. Estos hallazgos ponen de relieve el importante papel del níquel (III) en la catálisis.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis de la catálisis.
Química del níquel Química del níquel

Sus antecedentes:

Los complejos de níquel son catalizadores vitales para la formación de enlaces C-C y C-heteroatomo.
Mientras que el Ni(0) y el Ni(II) son comunes, se proponen intermediarios del Ni(I) y del Ni(III) en algunas reacciones.

Objetivo del estudio:

Para aislar, caracterizar e investigar la reactividad de los complejos de níquel (III).
Proporcionar evidencia de la participación del níquel (III) en el acoplamiento cruzado catalítico y la formación de enlaces heteroatómicos C.

Principales métodos:

Aislamiento y caracterización estructural de los complejos de Ni (III).
Análisis espectroscópico de las especies de Ni (III).
Evaluación de la reactividad organometálica, incluida la transmitación y la eliminación reductiva.
Prueba de la actividad catalítica en las reacciones de acoplamiento cruzado de Kumada y Negishi.

Principales resultados:

Se aislaron y caracterizaron con éxito complejos de Ni (III) con ligandos arilo y alquilo.
Se ha demostrado que estas especies de Ni (III) participan en la transmesación y eliminación reductiva.
Los complejos de Ni (III) confirmados son catalizadores competentes para las reacciones de acoplamiento cruzado de Kumada y Negishi.
Las especies observadas de Ni (III) facilitan la formación de enlaces C-C y C-heteroatomo.

Conclusiones:

Las especies organometálicas de Ni (III) están directamente involucradas en las reacciones de acoplamiento cruzado.
Los intermediarios de Ni (III) juegan un papel clave en la formación de enlaces heteroatómicos C inducidos oxidativamente.
Este trabajo proporciona una fuerte evidencia de la utilidad catalítica de Ni (III) en la síntesis orgánica.

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