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Updated: Jul 5, 2026
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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
El radical catiónico aislable del disileno: síntesis, caracterización y un sistema redox reversible de un electrón
Shigeyoshi Inoue1, Masaaki Ichinohe, Akira Sekiguchi
1Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan.
Journal of the American Chemical Society
|April 22, 2008
Resumen
Los disilenos altamente retorcidos pueden ser oxidados a radicales catiónicos estables. Estos radicales exhiben propiedades estructurales y electrónicas únicas, estabilizadas por hiperconjugación y espín deslocalizado.
Área de la Ciencia:
- Química del organosilicio Química del organosilicio
- Química Radical La Química Radical es una ciencia
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Los disilenos son análogos de silicio de los alquenos, que presentan un doble enlace Si = Si.
- Los disilenos altamente sustituidos pueden adoptar conformaciones retorcidas, lo que influye en sus propiedades electrónicas.
Objetivo del estudio:
- Para sintetizar y caracterizar un radical catiónico estable derivado de un disileno altamente retorcido.
- Para investigar las propiedades estructurales, electrónicas y redox del radical catiónico del disileno.
Principales métodos:
- Oxidación de un electrón de tetracis ((di-tert-butylmethylsilyl) disileno mediante el uso de Ph3C+.BAr4-.
- Aislamiento y cristalografía de rayos X de la sal de borato radical catión disileno resultante.
- Espectroscopia de resonancia paramagnética de electrones (EPR) para estudiar la deslocalización del espín.
Principales resultados:
- El radical catiónico del disileno fue sintetizado con éxito y aislado como una sal de borato estable.
- La cristalografía de rayos X reveló una estructura muy retorcida con un enlace Si-Si alargado.
- Los estudios EPR confirmaron la deslocalización del espín sobre los átomos centrales Si-Si, estabilizados por la hiperconjugación sigma-pi.
Conclusiones:
- Los disilenos altamente retorcidos pueden formar radicales catiónicos notablemente estables.
- La estabilidad se atribuye a la hiperconjugación y a una significativa deslocalización del espín.
- Se demostró un sistema redox reversible que involucra al disileno, su radical catiónico y el radical aniónico.
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