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La polimerización de la metátesis de apertura de anillo cis-selectiva con catalizadores de rutenio.
Benjamin K Keitz1, Alexey Fedorov, Robert H Grubbs
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|January 14, 2012
Resumen
Los catalizadores basados en rutenio permiten la polimerización de metátesis de apertura de anillo cis-selectiva de alquenos cíclicos. El contenido de polímero cis, que alcanza el 96%, es sintonizable a través de la estructura monomérica y el control de la temperatura de polimerización.
Área de la Ciencia:
- Química de Polímeros La química de los polímeros es la química de los polímeros.
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
Sus antecedentes:
- La polimerización por metástasis de apertura de anillo (ROMP) es un método versátil para la síntesis de polímeros.
- Lograr una alta cis-selectividad en ROMP es crucial para adaptar las propiedades del polímero.
- Los catalizadores basados en rutenio ofrecen reactividad ajustable y selectividad en las reacciones de metástasis.
Objetivo del estudio:
- Informar sobre la polimerización de metátesis de apertura de anillo cis-selectiva de varios alquenos monocíclicos y monómeros de tipo norborneno.
- Para investigar la influencia de la estructura del monómero y la temperatura en el contenido cis del polímero.
- Para demostrar la eficacia de un catalizador basado en rutenio activado por C-H para la polimerización controlada.
Principales métodos:
- Utilizó un catalizador de metátesis basado en rutenio activado por C-H.
- Se realizó la polimerización de la metátesis de apertura de anillo en diversos alquenos monocíclicos, norborenos y derivados de oxanorborenos.
- Temperatura de polimerización variada y estructura monomérica para estudiar sus efectos en la estereoquímica de polímeros.
Principales resultados:
- Se logró la polimerización de metátesis de apertura de anillo cis-selectiva de los monómeros estudiados.
- Se demostró que el contenido cis de los polímeros resultantes está significativamente influenciado por la estructura del monómero y la temperatura de reacción.
- Se obtienen polímeros con un alto contenido de cis, hasta el 96%, optimizando las condiciones de polimerización, específicamente reduciendo la temperatura.
Conclusiones:
- El catalizador basado en rutenio desarrollado promueve efectivamente la ROMP cis-selectiva.
- La estereoquímica de polímeros en ROMP se puede controlar con precisión ajustando el diseño del monómero y la temperatura de reacción.
- La reducción de la temperatura de polimerización es una estrategia clave para maximizar la selectividad cis en ROMP.
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