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Complejos Eta2-organoazida de níquel y su conversión en complejos imido terminales a través de la extrusión de
Rory Waterman1, Gregory L Hillhouse
1Gordon Center for Integrative Science, Department of Chemistry, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|August 30, 2008
Resumen
Las reacciones catalizadas por níquel de azidas orgánicas producen aductos de azidas estables. Estos intermediarios se transforman fácilmente en complejos de imido terminales a través de la extrusión de dinitrógeno al calentarse.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Catálisis de níquel y níquel.
- Química de las azidas Química de las azidas
Sus antecedentes:
- Los complejos de organo-níquel son valiosos catalizadores en la síntesis orgánica.
- Las azidas orgánicas son precursores versátiles de compuestos que contienen nitrógeno.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevos aductos de níquel-azido.
- Investigar la reactividad de estos adductos hacia la formación del complejo imido.
Principales métodos:
- Reacción de [{dtbpe) Ni]2{eta2-mu-C6H6) con 1-adamantilazida y mesitilazida.
- Aislamiento y caracterización cristalográfica de los aductos de azida resultantes.
- Estudios de termólisis para determinar la vía de descomposición.
Principales resultados:
- Los aductos estables de azida eta2-orgánica, (dtbpe) Ni(eta2-N3R), fueron sintetizados con éxito y caracterizados para R = adamantilo y mesitilo.
- Estos aductos fueron identificados como intermediarios clave en la formación de complejos de imido terminal.
- La pérdida intramolecular de nitrógeno se observó en la termólisis leve de los aductos de azida.
Conclusiones:
- El estudio demuestra una nueva ruta a los complejos de imido terminal ligados al níquel a través de aductos de azida.
- Los hallazgos proporcionan información sobre el mecanismo de extrusión de dinitrógeno en sistemas organometálicos.
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