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Síntesis selectiva de éteres de Z-silenoles a través de la funcionalización remota de cetonas catalizadas por Ni

Sinem Guven¹, Gourab Kundu¹, Andrea Weßels¹

¹Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany.

Journal of the American Chemical Society

|May 25, 2021

Resumen

Este estudio introduce un nuevo método de funcionalización remota catalizada por níquel para la síntesis de éteres de sililenoles. El proceso utiliza la marcha en cadena para lograr la selectividad Z, ofreciendo un control preciso sobre la formación del producto.

Área de la Ciencia:

Química orgánica
Catálisis
Química organometálica

Sus antecedentes:

Los éteres de sililenoles son productos intermedios sintéticos muy versátiles.
El logro de la funcionalización regioselectiva de las cetonas sigue siendo un desafío.
Las estrategias de funcionalización remota ofrecen nuevas posibilidades sintéticas.

Objetivo del estudio:

Desarrollar una nueva síntesis Z-selectiva de éteres de sililenoles.
Para lograr la funcionalización remota de las cetonas (hetero) aromáticas y alifáticas.
Para aclarar el mecanismo de la caminata en cadena catalizada por el níquel.

Principales métodos:

Funcionalidad remota catalizada por níquel.
La cadena de las olefinas.
Síntesis de éteres de enol de silicio.

Principales resultados:

Se logró una síntesis Z-selectiva de éteres de sililenoles.
La reacción se lleva a cabo a través de una cadena catalizada por níquel a partir de una olefina distante.
La selectividad posicional está dictada por la direccionalidad de la cadena.
Los estudios mecanicistas identificaron los principales intermediarios catalíticos, incluidos un dímero de Ni (I) y una especie de Ni (II) -H.

Conclusiones:

La estrategia desarrollada permite una funcionalidad remota eficiente.
El método proporciona una síntesis Z-selectiva de éteres de sililenoles.
Los conocimientos mecanicistas revelan el papel de los productos intermedios del níquel en el control de la selectividad.

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