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Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

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Reactividad de la funcionalización C-H de un níquel-imido

Stefan Wiese¹, Jason L McAfee, Dale R Pahls

¹Department of Chemistry, Georgetown University, Box 571227-1227, Washington, DC 20057, USA.

Journal of the American Chemical Society

|May 24, 2012

Resumen

Este estudio revela que un complejo de níquel (III) -imida exhibe una doble reactividad, experimentando la abstracción del átomo de hidrógeno y compitiendo con su producto de amida por los radicales resultantes en las reacciones de aminación C-H.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis es la catálisis.
Síntesis orgánica La síntesis orgánica.

Sus antecedentes:

Los complejos de níquel son catalizadores versátiles en las transformaciones orgánicas.
Comprender las vías de reactividad es crucial para diseñar sistemas catalíticos eficientes.

Objetivo del estudio:

Para investigar la reactividad bifuncional de un complejo β-diketiminato Ni (III) -imida.
Para dilucidar el mecanismo de las reacciones de aminación C-H que involucran a este complejo.

Principales métodos:

Reacciones de abstracción del átomo de hidrógeno (HAA) con sustratos bencílicos.
Estudios cinéticos. estudios de la cinética.
Cálculos de la Teoría Funcional de la Densidad (DFT).

Principales resultados:

El complejo Ni (III) -imida se somete a HAA con sustratos bencílicos.
Competencia observada entre el Ni (III) -imida y su producto Ni-amida para los radicales hidrocarbílicos.
Se observó la formación de aminas funcionalizadas y imidas de dinickel.

Conclusiones:

El mecanismo de aminación C-H implica la limitación de la tasa de HAA por el Ni (III) -imida.
Una competencia fundamental entre las especies imida y amida dicta la distribución del producto.
Destaca la importancia de las vías de rebote radical en la funcionalización C-H.

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