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Estereoquímica de la reducción de imina por un hidruro de rutenio hidroxiciclopentadienil rutenio
Charles P Casey1, Galina A Bikzhanova, Ilia A Guzei
1Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA. casey@chem.wisc.edu
Journal of the American Chemical Society
|February 16, 2006
Resumen
La transferencia de hidrógeno de un complejo de rutenio a las iminas N-arilo es en su mayoría trans estereospecífica, formando complejos de aminas. Sin embargo, la transferencia a las iminas N-alquilo es estereorrandomizada debido a una reversibilidad más rápida.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La estereoquímica es la estereoquímica.
- Mecanismos de reacción Mecanismos de reacción
Sus antecedentes:
- Los complejos de rutenio son catalizadores versátiles en la síntesis orgánica.
- La comprensión de los mecanismos de transferencia de hidrógeno es crucial para el desarrollo de procesos catalíticos eficientes.
- El resultado estereoquímico de la transferencia de hidrógeno puede ser influenciado por la estructura del sustrato.
Objetivo del estudio:
- Para investigar la estereoquímica de la transferencia de hidrógeno de un complejo específico de rutenio a diferentes sustratos de imina.
- Para aclarar las vías mecanicistas que rigen la estereospecificidad en estas reacciones.
Principales métodos:
- Síntesis del complejo de deuteruro de rutenio [2,5-Ph(2)-3,4-Tol(2)(eta(5)-C(4) COD) ]Ru(CO)(2) D.
- Reacción del complejo de rutenio con las iminas N-arilo y N-alquilo.
- Análisis del resultado estereoquímico de los complejos de aminas resultantes.
Principales resultados:
- La transferencia de hidrógeno a las N-aril iminas se produjo con una alta estereospecificidad trans.
- Un mecanismo propuesto implica la formación de un intermediario de rutenio coordinativamente insaturado y una coordinación rápida de aminas.
- La transferencia de hidrógeno a las N-alquiliminas dio lugar a productos estereorandómicos, lo que sugiere una reversibilidad más rápida que la coordinación de aminas.
Conclusiones:
- El resultado estereoquímico de la transferencia de hidrógeno catalizada por rutenio es altamente dependiente del sustrato de imina.
- La rápida coordinación del producto de aminas es clave para mantener la estereospecificidad con las iminas N-arilo.
- La reversibilidad de la transferencia de hidrógeno juega un papel crítico en la determinación de la estereoselectividad con las iminas N-alquilo.
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