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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

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Published on: August 16, 2018

Difuncionalización catalizada por níquel de alquenos no activados iniciada por enolados no estabilizados

David Huang¹, Diego Olivieri¹, Yang Sun¹

¹Department of Chemistry , Yale University , 225 Prospect Street , New Haven , Connecticut 06520-8107 , United States.

Journal of the American Chemical Society

|September 27, 2019

Resumen

Este estudio muestra que la catálisis del níquel puede difuncionalizar alquenos no activados utilizando enolados no estabilizados. La reacción funciona con varios electrófilos, permitiendo nuevas vías sintéticas.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los alquenos no activados suelen ser sustratos difíciles para las reacciones de difuncionalización.
La iniciación del nucleófilo enolado ofrece un enfoque mecanicista distinto para la funcionalización del alqueno.

Objetivo del estudio:

Para demostrar una nueva difuncionalización catalizada por níquel de alquenos no activados.
Explorar el alcance de los electrófilos compatibles con esta nueva metodología.

Principales métodos:

Reacción catalizada por níquel que emplea un nucleófilo enolado no estabilizado.
Utilizando un ligando de fosfina con deficiencia de electrones y un aditivo de sal de tetrabutilamonio.
Prueba de una amplia gama de arilo, heteroarilo, alqueno y amino electrófilos.

Principales resultados:

Se logró la difuncionalización exitosa de alquenos no activados.
La reacción demostró un amplio alcance de sustrato, tolerando varios electrófilos.
La combinación de un ligando específico de fosfina y un aditivo fue clave para la eficiencia.

Conclusiones:

Se ha desarrollado una nueva difuncionalización catalizada por níquel de alquenos no activados.
Este método proporciona una ruta versátil para la introducción de grupos funcionales vecinos.
Los hallazgos amplían la utilidad sintética de la química enolada en la catálisis.

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