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Complejos estables al aire (fenilbuta-1,3-diynyl) paladio (II): iniciadores altamente activos para la polimerización

Ya-Xin Xue¹, Yuan-Yuan Zhu, Long-Mei Gao

¹Department of Polymer Science and Engineering, School of Chemical Engineering, Hefei University of Technology and Anhui Key Laboratory of Advanced Functional Materials and Devices , Hefei 230009, China.

Journal of the American Chemical Society

|March 11, 2014

Resumen

Los complejos de paladio estable en el aire (II) inician la polimerización viva de los isocyanuros, dando lugar a poliisocianuros bien definidos. Este método versátil controla el peso molecular y permite la síntesis de copolímero en bloque.

Área de la Ciencia:

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

Sus antecedentes:

Los complejos de paladio son catalizadores cruciales en la síntesis orgánica.
Las técnicas de polimerización viva/controlada son esenciales para el control preciso de la estructura del polímero.

Objetivo del estudio:

Diseñar y sintetizar nuevos complejos de paladio (II) estables al aire (fenilbuta-1,3-diynyl).
Investigar su eficacia para iniciar la polimerización viva/controlada de los isocyanuros.
Explorar la versatilidad y las aplicaciones de los poliisocianuros resultantes.

Principales métodos:

Fácil síntesis de complejos de paladio (II).
Caracterización estructural utilizando RMN, EM y análisis de rayos X.
La polimerización viva/controlada de varios monómeros de isocyanuro iniciada por complejos de paladio.

Principales resultados:

Sintetizó con éxito complejos de paladio estable en el aire (II). complejos.
Se logró la polimerización viva/controlada de isocyanuros de fenilo, produciendo polímeros con pesos moleculares controlados y distribuciones estrechas.
Se ha demostrado una alta estereoregularidad en poli (fenilisocianuro) y la capacidad de formar copolímeros de bloque.
Se identificó que los grupos donantes de electrones mejoran la actividad catalítica.
Mostró una amplia gama de monómeros, incluidos los isocyanuros alquilo y estérico obstaculizados.
Sintetizó complejos multifuncionales de paladio para poliisocianuros en forma de estrella y telecélicos.

Conclusiones:

El sistema catalizado por paladio desarrollado ofrece una ruta versátil a los poliisocianuros bien definidos.
El método de polimerización permite un control preciso sobre la arquitectura del polímero, el peso molecular y la secuencia.
Este enfoque es aplicable a una amplia gama de isocyanuros y puede producir estructuras poliméricas complejas.

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