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Formación, estructura y detección de EPR de una especie Fe(IV) -oxo de alto espín derivada de un complejo Fe(III)
David C Lacy1, Rupal Gupta, Kari L Stone
1Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025, USA.
Journal of the American Chemical Society
|August 14, 2010
Resumen
Se desarrolló un nuevo complejo sintético de alto espín de oxoirón (IV), que ofrece una nueva vía a partir de especies de oxoirón (III) o hidroxoirón (III). Este avance proporciona una nueva herramienta para el estudio de las metalloenzimas no hemo.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Química bioorgánica Química bioorgánica.
- Química de las metaloproteínas
Sus antecedentes:
- Los complejos de alto espín de oxohierro (IV) son intermediarios cruciales en las metalloenzimas no hemo.
- Estudios sintéticos anteriores detectaron con éxito tales complejos en sólo dos sistemas.
- La comprensión de estos intermediarios es clave para elucidar los mecanismos de las enzimas.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo complejo de alto espín de oxohierro (IV). complejo.
- Explorar nuevas rutas sintéticas para las especies de alto espín de oxoirón (IV).
- Para investigar las propiedades estructurales y espectroscópicas de este nuevo complejo.
Principales métodos:
- Síntesis del complejo de oxoirón (IV) a partir de los precursores de oxoirón (III) y hidroxoirón (III).
- Caracterización mediante espectroscopia FTIR, Mossbauer, UV-Vis y EPR.
- Difracción de rayos X para la determinación estructural.
Principales resultados:
- Se preparó con éxito un nuevo complejo sintético de alto espín de oxoirón (IV) complejo.
- El complejo fue caracterizado por métodos espectroscópicos, confirmando su estado de oxidación Fe (IV) y su estado de espín S = 2.
- La cristalografía de rayos X reveló una geometría bipyramidal trigonal con un largo enlace Fe(IV) -O (1.680(1) Å).
- La espectroscopia EPR proporcionó las primeras características observables de EPR en modo paralelo para tales complejos.
Conclusiones:
- Se estableció una nueva ruta sintética para los complejos de alto espín de oxohierro (IV), incluido el primer proceso de transferencia de electrones acoplado a protones.
- El complejo caracterizado sirve como un modelo valioso para los intermediarios en las metalloenzimas no hemo.
- Se demuestra que la espectroscopia EPR es un método viable para la caracterización de los complejos de alto espín de oxoirón (IV).
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