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Ajuste de la formación de enlaces múltiples uranio-nitrógeno con los ligandos silóxido auxiliares
Clément Camp1, Jacques Pécaut, Marinella Mazzanti
1Laboratoire de Reconnaissance Ionique et Chimie de Coordination, SCIB, UMR-E3 CEA-UJF, INAC, CEA-Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 09.
Journal of the American Chemical Society
|August 7, 2013
Resumen
Este estudio detalla la síntesis y caracterización de nuevos complejos de siloxido de uranio. Las reacciones con azidas producen diversos complejos de imido, nitrido y azido de uranio, lo que pone de relieve el papel del entorno de coordinación en la química del uranio.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química del Uranio La Química del Uranio
- Coordinación Química de la Coordinación
Sus antecedentes:
- Las propiedades electrónicas únicas del uranio hacen que sea un elemento fascinante para la investigación química.
- Comprender la reactividad de los complejos de uranio de baja valencia es crucial para desarrollar nuevas metodologías sintéticas.
Objetivo del estudio:
- Para explorar la reactividad de los complejos homoleptos de uranio (III) siloxido con varios azidos.
- Para sintetizar y caracterizar nuevos complejos de imido, nitrido y azido de uranio.
- Investigar la influencia del entorno de coordinación en los resultados de la reacción.
Principales métodos:
- Síntesis de complejos de siloxido de uranio (III) a través de la reducción de los precursores de uranio (IV).
- Reacción de los silóxidos de uranio con azidas orgánicas e inorgánicas (por ejemplo, azida de adamantilo, azida de trimetilsililo, azida de cesio).
- Aislamiento y caracterización de productos utilizando cristalografía de rayos X y otras técnicas analíticas.
Principales resultados:
- Aislamiento de un complejo homoleptico de uranio (III) silóxido [K 18 c 6] [U OSi O Bu t 3 4].
- Síntesis de complejos dinucleares de U(VI) imido, U(V) imido, U(IV) azido y U(V) nitrido.
- Caracterización estructural que revela una "interacción catión-catión" en un complejo U(VI) y un raro núcleo U2N2 en un complejo de nitrido U(V).
- Formación de un complejo de diuranio (IV) con un ligando de nitrido puente y un catión de cesio.
Conclusiones:
- El entorno de coordinación dicta significativamente la vía de reacción y los productos cuando los siloxidos de U (III) reaccionan con las azidas.
- Se puede acceder a diversos estados de oxidación y motivos estructurales (imido, nitrido, azido).
- Este trabajo amplía la química conocida de los complejos de uranio de baja valencia y sus transformaciones.
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