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P- y m-[Bu2MeSi]2Si]2C6H4 aislables: disilaquinodimetano frente al triple bis (radical silílico)
Takeshi Nozawa1, Michiyo Nagata, Masaaki Ichinohe
1Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan.
Journal of the American Chemical Society
|March 30, 2011
Resumen
Se sintetizaron y estudiaron dos disilaquinodimetanos isoméricos. Un isómero exhibe una estructura quinodimethane singlet, mientras que el otro muestra una naturaleza biradical del estado fundamental triple.
Área de la Ciencia:
- Química del organosilicio Química del organosilicio
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los disilaquinodimetanos son análogos de silicio de los quinodimetanos.
- Comprender su estructura electrónica es crucial para el desarrollo de nuevos materiales basados en silicio.
Objetivo del estudio:
- Para sintetizar y caracterizar estructuralmente los isómeros para- y meta-disilaquinodimetanos.
- Para aclarar las propiedades electrónicas y estructurales de estos nuevos compuestos.
Principales métodos:
- Deshalogenación reductora de los bis (halosil) benzenos.
- Estudios de difracción de rayos X. Estudios de difracción de rayos X.
- Espectroscopia de resonancia magnética nuclear (RMN) en estado sólido.
- Mediciones de resonancia paramagnética de electrones (EPR, por sus siglas en inglés).
Principales resultados:
- Síntesis y aislamiento de dos isómeros disisilaquinodimetanos.
- Caracterización de un isómero como un quinodimethane singlet con contribución birradical.
- Identificación del otro isómero como un tripleto de estado básico bis ((radical silílico).
Conclusiones:
- Se determinaron las distintas estructuras electrónicas de los isómeros.
- Las propiedades estructurales y electrónicas están influenciadas por la disposición isomérica.
- Estos hallazgos contribuyen a la comprensión de los enlaces dobles silicio-carbono y de las especies birádicas.
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