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Metátesis de cierre de anillo de ciclopropanación y cierre de anillo en tándem de las dieninas
Brian P Peppers1, Steven T Diver
1Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, USA.
Journal of the American Chemical Society
|August 5, 2004
Resumen
Los catalizadores de rutenio permiten un nuevo ciclo de arreglo de las dieninas. Este tándem de ciclopropanación y metátesis de alqueno de cierre de anillo crea estructuras cíclicas únicas de manera eficiente.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- La metátesis de Enyne es una herramienta poderosa para la formación de enlaces carbono-carbono.
- Los catalizadores de rutenio son ampliamente utilizados en las reacciones de metástasis de olefinas.
Objetivo del estudio:
- Para explorar una nueva reacción de cicloarreglo de las dieninas.
- Investigar el uso de precatalizadores de rutenio carbeno y no carbeno en esta transformación.
Principales métodos:
- Reacción de metátesis de alqueno en tándem por ciclo-propanación/cerramiento del anillo.
- Se utilizan precatalizadores de rutenio carbeno y no carbeno rutenio (II).
- Estudios mecanicistas para proponer vías de reacción.
Principales resultados:
- Se logró la ciclorreorganización de las dieninas a través de un proceso de metátesis de alqueno de ciclopropanación/cerramiento de anillo en tándem.
- Se han identificado presuntos intermediarios de ciclopropilcarbenos.
- Se ha demostrado la formación exitosa de productos mediante la aplicación secuencial de catalizadores.
Conclusiones:
- El método desarrollado ofrece una nueva variación de la metátesis enyne.
- El proceso es desencadenado por precatalizadores específicos de rutenio.
- Se proporcionaron conocimientos mecánicos sobre la reacción en tándem.
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