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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
Un catalizador altamente activo para las reacciones de aminación catalizadas por Pd: reacciones de acoplamiento
Brett P Fors1, Donald A Watson, Mark R Biscoe
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|September 19, 2008
Resumen
Un nuevo ligando de la biarilmonofosfina, BrettPhos, permite reacciones eficientes de acoplamiento cruzado C-N utilizando mesilatos de arilo. Este sistema catalizador logra la monoariación selectiva de aminas y anilinas, incluso metilamina, con bajas cargas de catalizador.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Química organometálica Química orgánica de los metales.
Sus antecedentes:
- Las reacciones de acoplamiento cruzado C-N son fundamentales en la síntesis orgánica.
- El desarrollo de catalizadores eficientes para la arilación selectiva de aminas sigue siendo un desafío.
- Los mesilatos de arilo son socios de acoplamiento menos reactivos en comparación con otros electrófilos.
Objetivo del estudio:
- Informar de un nuevo sistema de catalizador basado en un ligando de biarylmonophosphine (BrettPhos) para el acoplamiento cruzado C-N.
- Demostrar la utilidad de los mesilatos de arilo como socios de acoplamiento en la formación de enlaces C-N.
- Para lograr una monoariación altamente selectiva de aminas alifáticas primarias y anilinas.
Principales métodos:
- Síntesis y caracterización del ligando de BrettPhos.
- Reacciones de acoplamiento cruzado C-N catalizadas por paladio utilizando BrettPhos.
- Investigación de la cinética de la reacción y la selectividad.
- Análisis estructural de complejos de adición oxidativa.
Principales resultados:
- El sistema de catalizador basado en BrettPhos exhibe una excelente reactividad en el acoplamiento cruzado C-N.
- Los mesilatos de arilo se emplean con éxito como socios electrófilos.
- Se logró una alta selectividad para la monoariación de aminas alifáticas primarias y anilinas.
- Se logró la primera monoarilación reportada de la metilamina.
- Se observaron bajas cargas de catalizador y tiempos de reacción rápidos.
Conclusiones:
- BrettPhos es un ligando altamente efectivo para las reacciones de acoplamiento cruzado C-N catalizadas por paladio.
- El sistema catalizador amplía el alcance de las reacciones de formación de enlaces C-N para incluir a los mesilatos de arilo.
- El ligando permite la monoariación selectiva de sustratos de aminas difíciles.
- La comprensión de los complejos de adición oxidativa proporciona una visión mecanicista de la alta reactividad del catalizador.
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