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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
Una clase de rutenio (II) catalizador para las hidrogenaciones asimétricas de transferencia de cetonas
Aidan M Hayes1, David J Morris, Guy J Clarkson
1Asymmetric Catalysis Group, Department of Chemistry, University of Warwick, UK.
Journal of the American Chemical Society
|May 19, 2005
Resumen
Un nuevo dímer de rutenio se convierte fácilmente en un catalizador monomérico activo para la hidrogenación de transferencia asimétrica. Este nuevo catalizador demuestra una actividad superior, enantioselectividad y estabilidad para la reducción de cetonas, incluso a bajas cargas.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Catalización asimétrica por catálisis asimétrica.
- Química verde es la química verde.
Sus antecedentes:
- Los complejos de rutenio son ampliamente utilizados en la catálisis.
- La hidrogenación de transferencia asimétrica (ATH) es crucial para la síntesis de compuestos quirales.
- El desarrollo de catalizadores altamente activos y selectivos sigue siendo un desafío clave.
Objetivo del estudio:
- Para investigar la conversión in situ de un dímero de rutenio a un catalizador monomérico de ATH.
- Para evaluar el rendimiento catalítico del catalizador monomérico derivado en la reducción de cetonas.
- Para comparar su actividad, enantioselectividad y estabilidad frente a sus análogos no atados.
Principales métodos:
- Síntesis del dímero 6 de rutenio a partir de TsDPEN en dos pasos.
- Generación in situ del catalizador monomérico 3 bajo condiciones de reducción de cetonas.
- Evaluación del rendimiento del catalizador utilizando varios sustratos cetónicos.
Principales resultados:
- El dímero de rutenio 6 se convierte eficientemente en catalizador monomérico 3 in situ.
- El catalizador 3 exhibe una actividad y enantioselectividad significativamente más altas que los derivados no atados.
- Se observó una alta estabilidad, con actividad a 0.01 mol% de carga y una rápida reducción (0.1 mol%) en 20 minutos a 80°C.
Conclusiones:
- El catalizador de rutenio monomérico 3 generado in situ es altamente efectivo para la hidrogenación de transferencia asimétrica.
- Su mayor rendimiento y estabilidad ofrecen una alternativa prometedora para una síntesis quiral eficiente.
- Las bajas cargas de catalizador y los rápidos tiempos de reacción contribuyen a procesos químicos más ecológicos.
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