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Azidación enantioselectiva catalizada por el hierro de ésteres β-ceto y oxindoles
Qing-Hai Deng1, Tim Bleith, Hubert Wadepohl
1Catalysis Research Laboratory, Im Neuenheimer Feld 584, 69120 Heidelberg, Germany.
Journal of the American Chemical Society
|March 30, 2013
Resumen
La azidación enantioselectiva catalizada por hierro de los ésteres beta-ceto y oxindoles se logró utilizando un nuevo reactivo de transferencia N3. Este método proporciona un acceso eficiente a valiosas azidas quirales con altas enantioselectividades.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Catalización asimétrica por catálisis asimétrica.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Las reacciones de azidación son cruciales para sintetizar compuestos que contienen nitrógeno.
- El desarrollo de métodos enantioselectivos para la azidación sigue siendo un desafío importante.
- La catálisis del hierro ofrece una alternativa rentable y sostenible a los catalizadores de metales preciosos.
Objetivo del estudio:
- Para informar el primer ejemplo de azidación enantioselectiva catalizada por Fe de ésteres beta-ceto y oxindoles.
- Introducir un reactivo de transferencia de N3 fácilmente disponible para la azidación asimétrica.
- Establecer una nueva ruta sintética para los ésteres quirales alfa-azido-beta-ceto y las 3-azidooxindolas 3-sustituidas.
Principales métodos:
- Condiciones de reacción catalizada por hierro.
- Utilizando un reactivo específico de transferencia de N3.
- Síntesis asimétrica de ésteres beta-ceto y oxindoles.
Principales resultados:
- Azidación enantioselectiva exitosa de ésteres beta-ceto y oxindoles.
- Se obtienen ésteres alfa-azido-beta-ceto con hasta un 93% de exceso enantiomérico (ee).
- Generó 3-azidooxindoles 3-sustituidos con altas enantioselectividades de hasta el 94% ee.
Conclusiones:
- Demostró la primera azidación enantioselectiva catalizada por Fe de ésteres beta-ceto y oxindoles.
- Valida la eficacia de un reactivo de transferencia de N3 fácilmente disponible en síntesis asimétrica.
- Proporcionó un nuevo método altamente enantioselectivo para acceder a valiosos compuestos quirales de azido.
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