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Reacciones radicales de un silene N-heterocíclico estable: estudio EPR y cálculo de DFT
Boris Tumanskii1, Pauline Pine, Yitzhak Apeloig
1Department of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Journal of the American Chemical Society
|June 24, 2004
Resumen
Los sililenos estables reaccionan con fuentes radicales para formar aductos. El electrón no emparejado en estos aductos se deslocaliza a través del anillo que contiene silicio, como lo muestra la espectroscopia EPR.
Área de la Ciencia:
- Química del organosilicio y su química.
- Química radical La química radical es una de las ciencias químicas más importantes.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Los sililenos estables son intermediarios reactivos del silicio.
- Los radicales libres son especies altamente reactivas.
Objetivo del estudio:
- Para investigar la reacción de un silileno estable con varias fuentes de radicales libres.
- Para caracterizar los añadidos radicales resultantes utilizando la espectroscopia de resonancia paramagnética electrónica (EPR).
Principales métodos:
- Reacción del 1,3-di-tert-butilo-1,3,2-diazasilol-2-ilideno con el TEMPO, Hg[P(O) ((OPri) ]2, (CO) 3CpM-MCp ((CO) 3 (M = W, Mo), (CO) 5Re-Re ((CO) 5 y el tolueno.
- Análisis de los productos de reacción mediante espectroscopia EPR.
Principales resultados:
- Formación de aductos radicales estables a partir de la reacción del silene con todas las fuentes radicales probadas.
- Los espectros EPR revelaron que el electrón no apareado está deslocalizado sobre el anillo de cinco miembros que contiene silicio.
Conclusiones:
- Los sililenos estables pueden atrapar efectivamente a los radicales libres para formar aductos radicales persistentes.
- La estructura electrónica de estos adductos se caracteriza por una deslocalización significativa del electrón no emparejado en el marco de sileno.
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