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Bis (((imino) piridina hierro (((II) cationes de alquilo para la polimerización de las olefinas
Marco W Bouwkamp1, Emil Lobkovsky, Paul J Chirik
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|July 7, 2005
Resumen
Los investigadores sintetizaron nuevos cationes de alquilo de hierro (II) utilizando un ligando único. Estos catalizadores son prometedores para la polimerización de etileno, produciendo polímeros de mayor peso molecular en comparación con los métodos tradicionales.
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:
- Los complejos de dialquilo ferroso de cinco coordenadas sirven como precursores para aplicaciones catalíticas.
- Los complejos de hierro ofrecen una alternativa potencialmente más sostenible a los catalizadores tradicionales.
Objetivo del estudio:
- Para sintetizar nuevos cationes de alquilo de hierro (II) con un ligando específico (iPrPDI).
- Para investigar la actividad catalítica de estos complejos de hierro en la polimerización de etileno.
Principales métodos:
- Tratamiento de un complejo dialquilo ferroso con una fuente de protones ([PhMe2NH][BPh4]) para formar cationes alquilo.
- Reacción con un ácido de Lewis (B(C6F5) 3) para inducir la abstracción de metido y generar un cation de hierro (II) alquilo libre de bases.
- Estudios de polimerización de etileno utilizando los catalizadores de hierro sintetizados.
Principales resultados:
- Formación de cationes alquilo de hierro (II) con un ligando donante coordinado en una geometría piramidal cuadrada distorsionada.
- Síntesis de un catión ferroso alquilo libre de bases activo para la polimerización del etileno.
- La polimerización de etileno utilizando el nuevo catalizador de hierro produjo polímeros con mayor peso molecular y una polidispersidad más estrecha que los de los catalizadores activados por metilalumoxano.
Conclusiones:
- Los nuevos cationes de hierro ((II) alquilo pueden sintetizarse y exhibir actividad catalítica.
- Los catalizadores de hierro desarrollados son efectivos para la polimerización de etileno, produciendo polímeros con características mejoradas.
- Esta investigación presenta una vía prometedora para el desarrollo de catalizadores avanzados de polimerización.
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