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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
A Ru catalizó la divergencia: ciclización oxidativa frente a la cicloisomerización de los alcoholes
1Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA.
Journal of the American Chemical Society
|March 14, 2002
Resumen
Los catalizadores de rutenio permiten reacciones distintas: ciclización oxidativa a delta-lactonas o cicloisomerización a dihidropiranos. La modificación del ligando altera drásticamente la formación del producto, mostrando vías sintéticas versátiles.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Los intermediarios de vinildeno de rutenio son clave en las reacciones catalíticas.
- La ciclización oxidativa de los alcoholes bis-homopropargílicos puede complicarse por vías de reacción alternativas.
Objetivo del estudio:
- Para investigar las reacciones catalíticas que involucran intermediarios de vinildeno de rutenio.
- Descubrir una nueva reactividad y controlar las vías de reacción a través de la modificación del catalizador.
Principales métodos:
- Se utilizan complejos de rutenio (II) con diferentes ligandos de fosfina (CpRu (p-CH3O-C6H4) 3P) 2Cl y CpRu (p-FC6H4) 3P) 2Cl).
- Empleado N-hidroxisuccinimida como un oxidante para la ciclización oxidativa.
- Investigó la influencia de la estructura del ligando en los resultados de las reacciones.
Principales resultados:
- El catalizador CpRu[(p-CH3O-C6H4) 3P]2Cl promovió la ciclización oxidativa para producir delta-lactonas.
- El cambio al catalizador CpRu[(p-FC6H4) 3P]2Cl redirigió la reacción a la cicloisomerización, formando dihidropiranos.
- Utilidad sintética demostrada mediante la síntesis de una feromona de mosquito y un precursor de un agente antiviral.
Conclusiones:
- La modificación de ligandos en catalizadores de rutenio proporciona una poderosa estrategia para controlar las vías de reacción.
- Este descubrimiento ofrece rutas sintéticas versátiles para moléculas orgánicas valiosas como delta-lactonas y dihidropiranos.
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