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La catálisis fotoredox con luz visible: las reacciones de aza-Henry a través de la funcionalización C-H

Allison G Condie¹, José C González-Gómez, Corey R J Stephenson

¹Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA.

Journal of the American Chemical Society

|January 15, 2010

Resumen

La catálisis fotoredox con luz visible permite la formación de enlaces C-C entre las N-arilaminas y los nitroalcanes. Esta reacción oxidativa aza-Henry acopla de manera eficiente los sustratos utilizando un catalizador de iridio y iones de iminio generados in situ.

Área de la Ciencia:

Química orgánica es la química orgánica.
La fotocatálisis por fotocatálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La formación de enlaces carbono-carbono es crucial en la síntesis orgánica.
La catálisis fotorredóxica de luz visible ofrece rutas sintéticas sostenibles.
Las N-arylaminas terciarias y los nitroalcanos son importantes componentes sintéticos.

Objetivo del estudio:

Desarrollar un nuevo método fotocatalítico de luz visible para la formación de enlaces C-C.
Para lograr la reacción oxidativa de aza-Henry entre las N-arilaminas terciarias y los nitroalcanes.
Para explorar el uso de fotocatalizadores de iridio en esta transformación.

Principales métodos:

Irradiación de luz visible.
Catalización por fotorredóxicas mediante el uso de un complejo de iridio (Ir(ppy) 2 ((dtbbpy) PF6).
Condiciones de reacción oxidativa de aza-Henry que emplean N-arylaminas y nitroalcanes terciarios.

Principales resultados:

Formación eficiente de enlaces C-C entre las N-arilaminas terciarias y los nitroalcanes.
Se obtuvieron altos rendimientos (hasta el 96%) de los productos deseados.
La reacción procedió a través de iones de iminio generados in situ.

Conclusiones:

El método desarrollado proporciona una nueva vía para la síntesis de valiosos compuestos orgánicos.
El mecanismo de reacción implica el enfriamiento reductor del estado excitado de iridio por la amina.
Es probable que la rotación del catalizador sea facilitada por el oxígeno atmosférico.

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