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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
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Síntesis de polímeros altamente cis y sindiotácticos a través de la polimerización de la metátesis de apertura de
Lauren E Rosebrugh1, Vanessa M Marx, Benjamin K Keitz
1Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|June 21, 2013
Resumen
Los catalizadores de rutenio permiten la polimerización de la metatesis de apertura de anillo para crear polímeros altamente cis y tácticos. Este avance ofrece un control preciso sobre la microestructura del polímero, logrando más del 95% de contenido cis y táctica en muchos casos.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Química organometálica Química orgánica de los metales.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La polimerización por metástasis de apertura de anillo (ROMP) es una técnica poderosa para la síntesis de polímeros.
- Lograr una alta selectividad cis y táctica simultáneamente en ROMP ha sido un desafío significativo.
- Los catalizadores de rutenio han demostrado ser prometedores en varias reacciones de polimerización.
Objetivo del estudio:
- Para informar el primer ejemplo de ROMP mediado por rutenio que produce polímeros altamente cis, altamente tácticos.
- Investigar la influencia de la estructura monomérica en el contenido cis y la táctica.
- Para explorar la microestructura de polímeros derivados de monómeros enantioméricamente puros.
Principales métodos:
- Utilizando catalizadores basados en rutenio para la polimerización de la metátesis de apertura de anillos.
- La síntesis de polímeros a partir de varios derivados del norboreneno.
- Analizar la microestructura del polímero utilizando técnicas para determinar el contenido de cis y la táctica (por ejemplo, espectroscopia de RMN).
Principales resultados:
- Se logró con éxito ROMP mediada por rutenio que produce polímeros con alto contenido de cis (>95% en algunos casos) y alta táctica (>95%).
- Se ha demostrado que el contenido cis depende de la estructura específica del monómero.
- La polimerización de 2,3-dicarboalcoxynorbornadieno enantioméricamente puro dio como resultado una microestructura sindiotáctica.
Conclusiones:
- Los catalizadores de rutenio son efectivos para sintetizar polímeros altamente cis, altamente tácticos a través de ROMP.
- El método desarrollado proporciona una nueva ruta para controlar con precisión la microestructura del polímero.
- Este avance abre posibilidades para crear materiales avanzados con propiedades a medida.
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