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Copolimerización catalítica de CO y etileno con un paladio neutro en carga (II) zwitterión
1Division of Chemistry and Chemical Engineering, Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|May 9, 2002
Resumen
Un nuevo complejo de paladio zwitteriónico, [Ph(2) BP(2)]PdMe(THF), muestra una sorprendente actividad catalítica en la copolimización de CO y etileno, que coincide con los sistemas catiónicos convencionales. Este descubrimiento avanza en la catálisis organometálica para la síntesis de policetona.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La ciencia de los polímeros es la ciencia de los polímeros.
- La catálisis es la catálisis.
Sus antecedentes:
- Los complejos zwitteriónicos ofrecen propiedades electrónicas únicas para la catálisis.
- Los complejos de paladio son ampliamente utilizados en la polimerización y copolimización de olefinas.
- Los ligandos de bis ((phosphino) borato proporcionan un soporte robusto para los centros metálicos.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo complejo de palladio zwitteriónico (II) complejo.
- Evaluar la actividad catalítica de este complejo en la copolimerización de CO y etileno.
- Para comparar su rendimiento con los catalizadores de paladio catiónico establecidos.
Principales métodos:
- Síntesis del complejo zwitteriónico Pd(II) utilizando un ligando bis(fosfino) borato.
- Pruebas catalíticas en la copolimización de monóxido de carbono y etileno.
- Caracterización de los policetones resultantes y comparación de los pesos moleculares.
- Estudios comparativos con sistemas de paladio catiónico.
Principales resultados:
- Síntesis exitosa del complejo zwitteriónico de paladio (II), [Ph (II) BP (II) ]PdMe (THF).
- El complejo zwitteriónico exhibe una actividad significativa en la copolimización de CO y etileno.
- La actividad catalítica y los pesos moleculares de las policetonas son comparables a los sistemas catiónicos.
- La naturaleza rica en electrones del sistema zwitteriónico no impide el rendimiento catalítico.
Conclusiones:
- Los complejos de paladio zwitteriónico pueden ser catalizadores efectivos para la copolimerización de CO/etileno.
- El ligando de bis ((phosphino) borato desarrollado apoya un catalizador de paladio altamente activo.
- Este trabajo amplía el alcance de los catalizadores para la síntesis de policetona, ofreciendo una alternativa potencialmente más estable a los sistemas catiónicos.
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