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La inserción reversible de alquenos en el enlace Pd-N de los Pd(II) -sulfonamidatos y sus implicaciones para las
Paul B White1, Shannon S Stahl
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
Journal of the American Chemical Society
|October 20, 2011
Resumen
La inserción de alquenos en enlaces de nitrógeno y paladio es crucial para la amidación oxidativa. Los amidatos ricos en electrones aceleran este paso clave de la reacción, lo que lleva a la formación eficiente de productos.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis por catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La inserción de alquenos en enlaces de nitrógeno y paladio es un paso fundamental en la amidación oxidativa catalizada por el paladio.
- Comprender los factores que influyen en esta reacción es clave para desarrollar sistemas catalíticos más eficientes.
Objetivo del estudio:
- Para preparar y caracterizar los complejos de paladio (II) -sulfonamidato.
- Para investigar el mecanismo de la inserción de alceno en los enlaces Pd-N.
- Para explorar la influencia de los efectos electrónicos en la reacción de inserción.
Principales métodos:
- Síntesis de complejos bien definidos de Pd (II) -sulfonamidato.
- Caracterización cristalográfica de los intermediarios Pd-amidato y Pd-alquilo.
- Estudios cinéticos y termodinámicos de la inserción de alceno.
- Estudios de efecto electrónico con el uso de variados ligandos de amidato.
Principales resultados:
- Los complejos de Pd (II) -sulfonamidato se someten a la inserción de un alqueno atado.
- Las especies de Pd-alquilo resultantes fueron caracterizadas cristalográficamente.
- La inserción de alqueno es reversible, pero el O ((2) impulsa la conversión completa a productos de aminación oxidativa.
- Los amidatos ricos en electrones favorecen cinéticamente y termodinámicamente la inserción de alceno en el enlace Pd-N.
Conclusiones:
- La inserción de alceno en enlaces Pd-N es un proceso reversible.
- Los amidatos ricos en electrones mejoran la velocidad y la favorabilidad de la inserción de alquenos.
- La amidación oxidativa catalizada por el paladio se puede lograr de manera eficiente con ligandos de amidato optimizados.
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