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La β'-funcionalización deshidrogenativa catalizada por paladio de los ésteres β-ceto con indolos a temperatura
Mikko V Leskinen1, Kai-Tai Yip, Arto Valkonen
1Department of Chemistry and NanoScience Center, University of Jyväskylä, FI-40014 JYU, Finland.
Journal of the American Chemical Society
|March 20, 2012
Resumen
Este estudio introduce una nueva reacción catalizada por paladio para la funcionalización de ésteres beta-ceto con indoles. El método logra una alta selectividad y buenos rendimientos en condiciones suaves, ofreciendo una nueva vía sintética.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis es la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Los ésteres beta-ceto y los indoles son importantes motivos estructurales en productos farmacéuticos y materiales.
- Los métodos eficientes para su funcionalización directa son cruciales para la química sintética.
- Los métodos existentes a menudo requieren condiciones duras o carecen de selectividad regional.
Objetivo del estudio:
- Desarrollar una nueva reacción de acoplamiento cruzado deshidrogenativo entre ésteres beta-ceto sustituidos por alfa e indolos.
- Lograr una alta selectividad regional para ambos socios de acoplamiento.
- Para establecer condiciones de reacción suaves utilizando la catálisis del paladio.
Principales métodos:
- Acoplamiento deshidrogenativo catalizado por el paladio.
- Utilizó ésteres beta-ceto sustituidos por alfa e indolos como sustratos.
- Empleó varios oxidantes bajo condiciones suaves a temperatura ambiente.
Principales resultados:
- Se logró una alta selectividad C3-regional para el componente indol.
- Se ha demostrado una alta beta'-regioselectividad para el componente beta-ceto éster.
- Se obtiene un buen rendimiento del producto en condiciones suaves a temperatura ambiente con varios oxidantes.
Conclusiones:
- El método desarrollado proporciona una ruta eficiente y selectiva para la síntesis de derivados funcionalizados de indol y éster beta-ceto.
- La reacción se lleva a cabo bajo una catálisis leve de paladio, lo que lo hace atractivo para la síntesis de moléculas complejas.
- Se propusieron dos posibles mecanismos de reacción, que difieren en el momento de la participación del indol.
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