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Acoplamiento deshidrogenativo de enlaces bencílicos y aldehídicos C-H

Tairin Kawasaki¹, Naoki Ishida¹, Masahiro Murakami¹

¹Department of Synthetic Chemistry and Biological Chemistry , Kyoto University , Katsura , Kyoto 615-8510 , Japan.

Journal of the American Chemical Society

|February 4, 2020

Resumen

La luz visible impulsa el acoplamiento deshidrogenativo catalítico de enlaces C-H en alquilbenzenos y N-metilamidas con aldehídos, formando valiosas cetonas alfa-arilo y alfa-amino. Esta reacción ofrece una vía directa a compuestos farmacológicamente relevantes.

Área de la Ciencia:

Química orgánica
Fotocatálisis
Activación de C-H

Sus antecedentes:

La funcionalización del enlace C-H es un desafío clave en la síntesis orgánica.
El desarrollo de métodos eficientes para la formación de enlaces C-C es crucial para la construcción de moléculas complejas.

Objetivo del estudio:

Para reportar una nueva reacción de acoplamiento deshidrogenativo fotoinducido.
Para permitir la síntesis de cetonas alfa-arilo y cetonas alfa-amino a partir de materiales de partida fácilmente disponibles.

Principales métodos:

Irradiación de alquilbenzenos o N-metilamidas con aldehídos en acetato de etilo utilizando luz visible.
Utilizando catalizadores de iridio y níquel para facilitar el proceso de activación y acoplamiento de C-H.

Principales resultados:

Formación de cetonas alfa-arilo mediante el acoplamiento de enlaces bencílicos C-H y enlaces aldehídicos C-H.
Síntesis de cetonas alfa-amino mediante el acoplamiento de enlaces C-H de N-metilamida y enlaces C-H aldehídicos.
Evolución del dihidrógeno como subproducto, lo que indica un proceso deshidrogenativo.

Conclusiones:

El método descrito proporciona una vía sencilla y eficiente para sintetizar valiosos derivados cetónicos.
Estas reacciones acceden a motivos estructurales con una relevancia farmacológica significativa.
Este enfoque fotocatalítico ofrece una alternativa sostenible para la formación de enlaces C-C.

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