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Activación C-H vinílica de estirenos por un complejo de hierro y aluminio

Nikolaus Gorgas^1,2, Benedek Stadler¹, Andrew J P White¹

¹Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, 82 Wood Lane, Shepherds Bush, London W12 0BZ, U.K.

Journal of the American Chemical Society

|February 2, 2024

Resumen

Este estudio demuestra la activación selectiva C-H de los estirenos utilizando un complejo bimetálico de hierro y aluminio. La nueva vía conduce a la metalización (E) -beta, lo que permite una mayor funcionalización de los alquenos.

Área de la Ciencia:

Química organometálica
Catálisis
Activación de C-H

Sus antecedentes:

La adición oxidativa de enlaces sp2 C-H en alquenos es un desafío debido a la coordinación pi competitiva.
Existen ejemplos y aplicaciones limitadas para este tipo de reactividad de alceno.

Objetivo del estudio:

Para reportar la activación C-H de los estirenos utilizando un complejo bimetálico Fe-Al.
Para aclarar el mecanismo de reacción y explorar una mayor funcionalidad.

Principales métodos:

Utilizó un complejo de Fe-Al bimetálico bien definido para las reacciones de activación de C-H.
Se emplearon estudios experimentales y computacionales para investigar la vía de reacción.
Se ha demostrado la funcionalización de alceno a través de la fosfinación (E) selectiva.

Principales resultados:

Se ha conseguido una metalización (E) -beta altamente selectiva de los estirenos.
Se identificó una vía de reacción inusual que involucra un intermediario de cicloadición (2+2) y una activación intramolecular de C-H en dos metales.
Se caracteriza por un estado de transición altamente asincrónico para el paso clave de escisión C-H.

Conclusiones:

El complejo bimetálico Fe-Al permite la activación selectiva C-H de los estirenos.
La unión de alceno es crucial para este sistema catalítico.
La vía de activación C-H descubierta ofrece nuevas posibilidades para la funcionalización de alquenos.

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