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Reactividad de TEMPO hacia los intermediarios de reacción organometálicos de 16 y 17 electrones: un estudio de IR con
Justin P Lomont1, Son C Nguyen, Charles B Harris
1Department of Chemistry, University of California, Berkeley, Berkeley 94720, California, USA.
Journal of the American Chemical Society
|July 4, 2013
Resumen
El radical (2,2,6,6-tetrametilpiperidin-1-il) óxilo (TEMPO) reacciona con los intermediarios organometálicos no saturados. TEMPO actúa como un ligando aniónico, coordinando a través de un mecanismo asociativo y oxidando el centro del metal.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La espectroscopia es una técnica de espectroscopia.
- Química computacional es la química computacional.
Sus antecedentes:
- El radical (2,2,6,6-tetrametilpiperidin-1-il) óxilo (TEMPO) es versátil en estudios de catálisis y biológicos.
- TEMPO exhibe diversos modos de coordinación cuando actúa como un ligando en complejos organometálicos.
Objetivo del estudio:
- Investigar la reactividad de TEMPO con intermedios de reacción organometálicos de 16 y 17 electrones coordinadamente insaturados.
- Caracterice el mecanismo de coordinación de TEMPO para los centros metálicos.
Principales métodos:
- Espectroscopia infrarroja ultra rápida con resolución de tiempo para monitorear las reacciones.
- Cálculos de la teoría funcional de la densidad (DFT) para interpretar espectros y analizar estructuras.
Principales resultados:
- Las coordenadas TEMPO a las especies de 16 electrones (CpCo, Fe, CO4) y 17 electrones (CpFe, CO2, Mn, CO5) a través de un mecanismo asociativo.
- Los adductos de TEMPO muestran que TEMPO actúa como un ligando aniónico con una geometría piramidal de nitrógeno.
- Los centros metálicos se oxidan en la coordinación TEMPO.
Conclusiones:
- Este estudio proporciona la primera caracterización directa del mecanismo de reacción de TEMPO con complejos organometálicos insaturados.
- Los resultados ofrecen información valiosa sobre las interacciones de TEMPO con los intermediarios de reacción comunes.
- La reactividad de TEMPO es consistente en varios complejos de metales de transición de baja valencia estudiados.
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