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09:58
Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Epoxidación asimétrica con H2O2 mediante la manipulación de las propiedades electrónicas de los catalizadores de
Olaf Cussó1, Isaac Garcia-Bosch, Xavi Ribas
1QBIS ResearchGroup, Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona , Campus Montilivi, Girona E-17071, Catalonia, Spain.
Journal of the American Chemical Society
|September 25, 2013
Resumen
Un nuevo catalizador de hierro no hemo permite la epoxidación altamente enantioselectiva de olefinas utilizando peróxido de hidrógeno (H2O2). Los aditivos de ácido carboxílico mejoran significativamente los excesos enantioméricos, lo que lleva a una síntesis eficiente de epoxidos valiosos.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Catalización asimétrica por catálisis asimétrica.
- Reacciones de oxidación Reacciones de oxidación.
Sus antecedentes:
- Los complejos de hierro no hemo se estudian cada vez más para la oxidación catalítica.
- La epoxidación enantioselectiva de las olefinas es crucial para la síntesis de compuestos quirales.
- El peróxido de hidrógeno (H2O2) es un oxidante atractivo y respetuoso con el medio ambiente.
Objetivo del estudio:
- Desarrollar un catalizador de hierro no hemo altamente enantioselectivo para la epoxidación de olefinas utilizando H2O2.2.
- Investigar el papel de los aditivos de ácido carboxílico en la mejora del rendimiento catalítico.
- Comprender los efectos electrónicos y sinérgicos que rigen el ciclo catalítico.
Principales métodos:
- Síntesis y caracterización de un nuevo complejo de hierro no hemo.
- Epoxidación catalítica de una amplia gama de olefinas utilizando H2O2.
- Optimización de las condiciones de reacción, incluyendo el uso de aditivos de ácido carboxílico.
- Análisis de excesos enantioméricos (ee) y rendimientos utilizando cromatografía quiral.
Principales resultados:
- El complejo de hierro no hemo catalizó efectivamente la epoxidación enantioselectiva de las olefinas con H2O2.2.
- La adición de cantidades catalíticas de ácidos carboxílicos mejoró significativamente los excesos enantioméricos.
- Los efectos ligandos electrónicos y los ácidos carboxílicos promovieron sinérgicamente la escisión eficiente de enlaces O-O.
- Se sintetizó una amplia gama de epoxidos con altos rendimientos y cortos tiempos de reacción.
Conclusiones:
- Un nuevo sistema de catalizador de hierro no hemo proporciona una epoxidación altamente enantioselectiva de las olefinas.
- Los aditivos de ácido carboxílico son clave para lograr altos excesos enantioméricos.
- El sistema catalizador ofrece un método valioso y eficiente para sintetizar epoxidos quirales.
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