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Preparación y C-X reactividad de eliminación reductora de los complejos monoaryl Pd(IV) -X en agua (X = OH, OH2, Cl,
Williamson Oloo1, Peter Y Zavalij, Jing Zhang
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Journal of the American Chemical Society
|September 28, 2010
Resumen
Nuevos complejos de paladio (IV) fueron sintetizados en agua a 0°C. Estos complejos se someten eficientemente a la eliminación reductora de haluros de arilo (Ar-X) a temperatura ambiente, mostrando tasas de reacción comparables.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Coordinación Química de la Coordinación
Sus antecedentes:
- Los complejos de paladio son vitales en la catálisis.
- La comprensión de la química del paladio es crucial para el desarrollo de nuevas reacciones catalíticas.
- La eliminación reductora es un paso clave en muchos ciclos catalíticos.
Objetivo del estudio:
- Para sintetizar nuevos complejos monohidrocarbil paladio (IV).
- Para investigar la eliminación reductora de haluros de arilo de estos complejos.
- Para determinar la cinética de la eliminación reductora con diferentes ligandos halogenados.
Principales métodos:
- Síntesis de complejos de paladio (IV) en medios acuosos a bajas temperaturas.
- Caracterización de los complejos sintetizados.
- Estudios cinéticos de las reacciones de eliminación reductora en agua a temperatura ambiente.
Principales resultados:
- Se prepararon con éxito complejos de monohidrocarbil paladio ((IV) con ligandos OH, OH ((2), Br y Cl en agua.
- Estos complejos exhibieron altos rendimientos de eliminación reductiva de Ar-X (X = OH, Br, Cl) en el agua.
- Se encontró que las constantes de velocidad para la eliminación reductora (k ((OH), k ((Cl), k ((Br)) eran de magnitud similar.
Conclusiones:
- El 1-hidroxi-1,1-bis(2-piridil) metóxido quelata fácilmente soporta complejos estables de paladio (IV).
- La eliminación reductora de estos complejos de paladio (IV) es eficiente y se produce en condiciones suaves.
- Las tasas de reacción similares sugieren un mecanismo común para la eliminación reductora independientemente del ligando halogenado.
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