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Las alquenilaciones C-H enantioselectivas de alcoholes secundarios catalizadas por iridio dirigidas al heteroarilo

Wenbin Mao¹, Craig M Robertson¹, John F Bower¹

¹Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, United Kingdom.

Journal of the American Chemical Society

|December 23, 2024

Resumen

Este estudio introduce una nueva reacción catalizada por iridio en la que los alcoholes secundarios se agregan a los alquinos, creando valiosos alcoholes terciarios alquinizados con alta selectividad. Este método de funcionalización C ((sp3) -H también se extiende a las reacciones de alquilación.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La funcionalización C ((sp3) -H es un área clave en la química sintética.
El desarrollo de métodos selectivos para crear estructuras complejas de alcohol sigue siendo un desafío.

Objetivo del estudio:

Desarrollar una nueva adición de alcoholes secundarios a los alquinos catalizados por iridio C ((sp3) -H.
Demostrar la utilidad de este método para la síntesis de alcoholes terciarios alquenizados.
Para explorar un proceso de alquilación relacionado C ((sp3) -H.

Principales métodos:

Reacciones catalizadas por iridio utilizando alcoholes secundarios sustituidos por 2-aza-arilo.
Reacciones de adición con varios alquinos y estireno.
Estudios mecanicistas que incluyen azaenolización dirigida.

Principales resultados:

Se obtuvieron altos rendimientos y una excelente regioselectividad y enantioselectividad mediante la adición de alcoholes a las alquinas.
Se confirmó la formación de alcoholes terciarios alquenizados.
Se demostró con éxito un prototipo de alquilación C ((sp3) -H utilizando estireno.

Conclusiones:

El proceso desarrollado catalizado por iridio proporciona una ruta eficiente a los alcoholes terciarios complejos.
La metodología ofrece una herramienta poderosa para la funcionalización de C ((sp3) -H.
Se propone la aza-enolización dirigida como la vía mecanicista clave.

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