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A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
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Reacciones de migración de nitrogrupos catalizadas por Rh2 (II): síntesis selectiva de 3-nitroindoles a partir de
Benjamin J Stokes1, Sheng Liu, Tom G Driver
1Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607-7061, USA.
Journal of the American Chemical Society
|March 16, 2011
Resumen
Los catalizadores de rodio facilitan la migración de grupos de retiro de electrones en azidas de estirilo, produciendo indoles 3-sustituidos. Esta reacción ofrece una ruta selectiva a valiosos derivados del indol.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Los derivados del indole son frecuentes en los productos farmacéuticos y en la ciencia de los materiales.
- Las rutas sintéticas eficientes para los indoles sustituidos son muy buscadas.
- Las reacciones de migración ofrecen vías únicas para la construcción molecular.
Objetivo del estudio:
- Desarrollar un nuevo método catalítico para sintetizar indoles 3-sustituidos.
- Investigar la aptitud migratoria de varios grupos de extracción de electrones en esta transformación.
- Para utilizar complejos de carboxilato de rodio como catalizadores eficientes.
Principales métodos:
- Utilizando complejos de carboxilato de rodio (1 mol %) como catalizadores.
- Reaccionando azidas de estirilo β-sustitutos con varios grupos de retiro de electrones.
- Analizando la regioselectividad de la migración del grupo de retirada de electrones.
Principales resultados:
- Formación selectiva de indoles 3-sustituidos a partir de azidos de estirilo β-sustituidos.
- Se estableció el orden relativo de la aptitud migratoria: éster ≪ amida < H < sulfonilo < benzoilo ≪ nitro.
- Demostró la eficiencia catalítica de los complejos de carboxilato de rodio.
Conclusiones:
- La migración catalizada por el rodio proporciona un método selectivo y eficiente para la síntesis de indoles.
- El orden de aptitud migratoria proporciona información valiosa para el diseño de sustratos.
- Esta metodología amplía el conjunto de herramientas para la construcción de complejas arquitecturas indole.
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