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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
Copolimización de éteres de vinilo silílico con olefinas por (alfa-diimina) PdR+
1Department of Chemistry, The University of Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|September 14, 2006
Resumen
Este estudio muestra que un catalizador de paladio puede copolimerizar olefinas y éteres de vinilo silílico. Los copolímeros resultantes pueden desiliarse para obtener copolímeros valiosos de alcohol vinílico.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La ciencia de los polímeros es la ciencia de los polímeros.
- La catálisis de la catálisis.
Sus antecedentes:
- La polimerización de las olefinas es una piedra angular de la química de los polímeros.
- La incorporación de diversos monómeros en las cadenas de polímeros sigue siendo un desafío.
- Los éteres de vinilo silyl ofrecen funcionalidades únicas para la modificación de polímeros.
Objetivo del estudio:
- Para investigar la copolimización de olefinas y éteres de vinilo silílico utilizando un catalizador de paladio.
- Para dilucidar el mecanismo de esta nueva reacción de copolimización.
- Explorar el potencial de los copolímeros resultantes para una mayor funcionalización.
Principales métodos:
- Utilizó un catalizador (alfa-diimina) PdMe+ para las reacciones de copolimización.
- Empleado varios éteres de silil vinilo y 1-hexeno como monómeros.
- Estructuras poliméricas analizadas mediante técnicas espectroscópicas.
- Realizó experimentos de control para descartar mecanismos alternativos.
Principales resultados:
- Se logró con éxito la copolimización del 1-hexeno con éteres de vinilo silílico (R=tBu, SiMe3).
- Propuso un mecanismo de inserción / caminata en cadena, distinto de las vías catiónicas o radicales.
- Demostró que los copolímeros pueden desiliarse para obtener copolímeros de alcohol vinílico.
- Se identificaron los principales patrones de incorporación de comonomeros en la estructura del copolímero.
Conclusiones:
- El catalizador (alfa-dimina) PdMe+ media efectivamente la copolimización de las olefinas y los éteres de vinilo silílico.
- El mecanismo de inserción/caminata en cadena propuesto proporciona una visión de la vía de reacción.
- La desilación de los copolímeros resultantes ofrece una ruta hacia materiales poli (olefin-co-alcohol vinílico) funcionales.
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