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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
Hidrogenólisis de los complejos de pinzas de palladio (II) hidróxido y metóxido de palladio
Gregory R Fulmer1, Richard P Muller, Richard A Kemp
1Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, USA.
Journal of the American Chemical Society
|January 29, 2009
Resumen
Los complejos de paladio se someten a hidrogenólisis para formar hidruro de paladio. Los estudios cinéticos y computacionales revelan que la reacción se produce a través de un intermediario de hidróxido monomérico y un mecanismo de transferencia de protones intramolecular de cuatro centros.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Química organometálica Química orgánica de los metales.
- Mecanismos de reacción Mecanismos de reacción
Sus antecedentes:
- Los complejos de paladio son catalizadores cruciales en varias transformaciones químicas.
- Comprender los mecanismos precisos de las reacciones catalizadas por el paladio es esencial para optimizar las rutas sintéticas.
- Las reacciones de hidrogenólisis que involucran complejos de paladio son de gran interés para la producción de valiosos productos químicos intermedios.
Objetivo del estudio:
- Para investigar la hidrogenólisis de los complejos de hidróxido y metóxido de palladio.
- Para dilucidar la vía de reacción e identificar los intermediarios clave.
- Para determinar el mecanismo preferido (transferencia intramolecular de protones frente a la adición oxidativa / eliminación reductora).
Principales métodos:
- Síntesis y caracterización de los complejos de hidróxido y metóxido de paladio (II)
- Estudios cinéticos de la reacción de hidrogenólisis con hidrógeno molecular (H2).
- Estudios computacionales (por ejemplo, cálculos de DFT) para modelar vías de reacción.
Principales resultados:
- La hidrogenólisis de los complejos de hidróxido y metóxido de palladio (II) produce el correspondiente hidróxido de palladio (II).
- En soluciones acuosas, el complejo 1 existe como un dímero con puente de agua.
- Los datos cinéticos indican que la reacción con H2 ocurre exclusivamente a través del monómero de hidróxido.
- El análisis computacional apoya un mecanismo de transferencia de protones intramoleculares de cuatro centros.
Conclusiones:
- La hidrogenólisis de los complejos de hidróxido y metóxido de paladio (II) procede a través de una vía distinta que involucra a los intermediarios monoméricos.
- Una transferencia de protones intramolecular de cuatro centros es el mecanismo favorecido sobre la adición oxidativa / eliminación reductora tradicional.
- Estos hallazgos proporcionan información crítica sobre la reactividad de las especies de hidruro de paladio.
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