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Reacciones en tándem de desplazamiento [1,2] catalizadas por bromuro de hierro en la aminación de enlaces C-H
Quyen Nguyen1, Tuyen Nguyen, Tom G Driver
1Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, IL 60607-7061, USA.
Journal of the American Chemical Society
|December 26, 2012
Resumen
El bromuro de hierro (II) cataliza la síntesis de indol a partir de azidas de arilo a través de la aminación C-H y un desplazamiento [1,2]. La reacción favorece al fenilo sobre los grupos alquilo o secundarios en el paso de desplazamiento.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Química Heterocíclica La Química Heterocíclica es una de las más conocidas.
Sus antecedentes:
- Las azidas de arilo son precursores versátiles en la síntesis orgánica.
- Los andamios de indole son frecuentes en productos farmacéuticos y productos naturales.
- La funcionalización C-H ofrece rutas sintéticas eficientes.
Objetivo del estudio:
- Desarrollar un nuevo método catalítico para la síntesis de indolos 2,3-disubstituidos.
- Para investigar el mecanismo de una reacción en tándem de aminación C-H/[1,2]-cambio.
- Para determinar el alcance del sustrato y la regioselectividad de la transformación.
Principales métodos:
- La catálisis con el uso de bromuro de hierro (II).
- Reacción de las azidas de arilo orto-sustituidas.
- Análisis de los intermedios y productos de la reacción en tándem.
Principales resultados:
- Síntesis exitosa de indolos 2,3-disubstituidos a partir de azidas de arilo.
- Demostración de una aminación de enlace C-H etéreo en tándem seguida de un desplazamiento [1,2].
- Preferencia establecida para el componente de desplazamiento [1,2]: Me < 1° < 2° < Ph.
Conclusiones:
- El bromuro de hierro (II) es un catalizador eficaz para la formación de indoles.
- La reacción en tándem proporciona una nueva ruta a los indoles sustituidos.
- La aptitud migratoria en el paso de desplazamiento [1,2] está influenciada por factores electrónicos y estéricos.
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