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Published on: September 7, 2019
Un complejo mononuclear de manganeso no hemo ((IV) -oxo que se une a iones metálicos redox-inactivos
Junying Chen1, Yong-Min Lee, Katherine M Davis
1Department of Bioinspired Science, Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea.
Journal of the American Chemical Society
|January 18, 2013
Resumen
Los iones metálicos inactivos redox como el escandio pueden alterar significativamente la reactividad del complejo manganeso-oxo. Este estudio muestra que Sc(3+) mejora la transferencia de átomos de oxígeno pero dificulta la transferencia de átomos de hidrógeno en sistemas de manganeso no hemo.
Área de la Ciencia:
- Química inorgánica y inorgánica.
- Química bioorgánica y bioorgánica.
- La catálisis de la catálisis.
Sus antecedentes:
- Los iones metálicos inactivos redox modulan la reactividad de las especies de metal-oxo de alta valencia.
- Los complejos de metales no hemo son cruciales en las oxidaciones enzimáticas y químicas.
Objetivo del estudio:
- Sintetice y caracterice un complejo mononuclear no-hemo Mn(IV) -oxo.
- Investigar el impacto de la unión de iones redox-inactivos de escandio en la reactividad de Mn(IV) -oxo.
- Compara los efectos en las reacciones de transferencia de átomos de oxígeno y transferencia de átomos de hidrógeno.
Principales métodos:
- Síntesis de un pentadentato N5-ligado con el complejo Mn(IV) -oxo.
- Complejación con iones de escandio (Sc3+).
- Caracterización espectroscópica (por ejemplo, UV-Vis, EPR).
- Estudios cinéticos de las reacciones de oxidación.
Principales resultados:
- Se sintetizó con éxito un nuevo complejo Mn(IV) -oxo que se une a Sc(3+).
- La unión de Sc(3+) aumentó dramáticamente la tasa de oxidación del tioanisole (~2200 veces) a través de la transferencia de átomos de oxígeno.
- La unión de Sc(3+) disminuyó significativamente la tasa de activación C-H del 1,4-ciclohexadieno (~180 veces) a través de la transferencia de átomos de hidrógeno.
Conclusiones:
- Demuestra el primer ejemplo de un complejo Mn(IV) -oxo no hemo influenciado por iones metálicos redox-inactivos.
- Destaca los efectos contrastantes de Sc(3+) en el oxígeno frente a los mecanismos de transferencia de átomos de hidrógeno.
- Proporciona información sobre el ajuste de la reactividad metal-oxó utilizando iones metálicos auxiliares.
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