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Activación mecánica de catalizadores para la formación de enlaces C-C y reacciones de polimerización aniónica a

Andrew G Tennyson¹, Kelly M Wiggins, Christopher W Bielawski

¹Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712, United States.

Journal of the American Chemical Society

|November 4, 2010

Resumen

El ultrasonido rompe mecánicamente los enlaces entre el paladio y el polímero, liberando polímeros funcionales para la catálisis y desenmascarando los catalizadores de paladio para nuevas reacciones. Esto demuestra un nuevo enfoque para la modificación y catálisis mecanoquímica de polímeros.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La ciencia de los polímeros es la ciencia de los polímeros.
Mecanoquímica es la mecanoquímica.

Sus antecedentes:

La funcionalización del polímero a menudo requiere condiciones químicas duras.
El desarrollo de materiales sensibles a estímulos es crucial para aplicaciones avanzadas.
Los complejos de paladio son catalizadores versátiles en la síntesis orgánica.

Objetivo del estudio:

Para sintetizar polímeros organometálicos mediante el acoplamiento de poli (metilacrilato) cubierto de piridina a un complejo de dipalladio.
Para investigar la respuesta mecanoquímica de estos polímeros a la ultrasonido.
Para explorar las aplicaciones catalíticas de los fragmentos de polímero y las especies de paladio desenmascaradas.

Principales métodos:

Síntesis de poli (metilacrilatos) cubiertos de piridina (PyP (M)).
El acoplamiento de PyP (M) con el complejo de dipalladio ciclometalizado de SCS (CH) (CN) (CN) (CN) (CN) (CN)) (C) (C) (C) (C) (C) (C) (C)) (C) (C) (C) (C) (C)) (C) (C) (C) (C) (C) (C) (C) (C)) (C) (C)) (C) (C) (C) (C) (C) (C) (C) (C) (C)) (C) (C) (C) (C)) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C) (C)
Ultrasonido de los polímeros organometálicos resultantes [(1)(PyP(M))(2) ].
Análisis espectroscópicos y macromoleculares.

Principales resultados:

Se han sintetizado con éxito polímeros organometálicos [{1}{2}PyP{3}M{4}2}]
La ecografía indujo la escisión mecánica de los enlaces piridina-paladio.
El PyP ((M) liberado fue utilizado para la desprotonación y la polimerización aniónica.
Las especies de paladio desenmascaradas catalizaban la formación de enlaces carbono-carbono.

Conclusiones:

Las fuerzas mecánicas de la ultrasonificación modifican de manera controlable los polímeros organometálicos.
Este trabajo presenta una nueva estrategia mecanoquímica para la funcionalización de polímeros y la activación de catalizadores.
El sistema desarrollado ofrece potencial para materiales sensibles a estímulos y catálisis controlada.

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