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Reacciones de aminación de enlaces C-H alifáticos intramoleculares catalizadas por Rh2 (II) utilizando azidas de
Quyen Nguyen1, Ke Sun, 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
|April 24, 2012
Resumen
Los catalizadores de rodio permiten la aminación C-H intramolecular utilizando azidas de arilo. Esta reacción funciona eficientemente enlaces alifáticos no activados con diversas fuentes de nitrógeno, ampliando las aplicaciones sintéticas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis es la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- La aminación C-H intramolecular es una transformación clave para la construcción de moléculas que contienen nitrógeno.
- Los métodos tradicionales a menudo requieren sustratos preactivados o condiciones duras.
- El uso de azidas de arilo como precursores del átomo de nitrógeno generalmente requiere grupos de retirada de electrones para una eficiente formación de nitreno metálico.
Objetivo del estudio:
- Desarrollar un nuevo sistema catalítico para la aminación intramolecular de enlaces alifáticos C-H no activados.
- Explorar el alcance de las azidas de arilo como fuentes de nitrógeno en la funcionalización C-H catalizada por rodio.
- Investigar el mecanismo de la aminación C-H catalizada por el rodio con diversas azidas de arilo.
Principales métodos:
- Empleando complejos de dicarboxilato de rodio (II) como catalizadores.
- Utilizando azidas de arilo como el precursor del átomo de nitrógeno.
- Reaccionando en enlaces C-H alifáticos primarios, secundarios y terciarios no activados bajo condiciones catalíticas.
Principales resultados:
- Catálisis exitosa de la aminación intramolecular de enlaces alifáticos C-H no activados.
- Demostración de la utilidad de las azidas de arilo ricas en electrones y pobres en electrones.
- Formación del intermedio reactivo del nitreno metálico a partir de una amplia gama de azidas de arilo.
Conclusiones:
- Los complejos de dicarboxilato de rodio (II) son catalizadores efectivos para la aminación C-H.
- La reacción procede de manera eficiente con diversos azidos de arilo, superando las limitaciones anteriores.
- Esta metodología proporciona una ruta versátil para sintetizar compuestos complejos que contienen nitrógeno.
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