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Pentasila-1,4-dieno: homoconjugación entre los enlaces dobles SiSi a través de una unidad SiMe(2)

Tomoyuki Kosai¹, Shintaro Ishida¹, Takeaki Iwamoto¹

¹Department of Chemistry, Graduate School of Science, Tohoku University , Aoba-ku, Sendai 980-8578, Japan.

Journal of the American Chemical Society

|December 20, 2016

Resumen

Los investigadores sintetizaron un pentasila-1,4-dieno estable, un compuesto que presenta enlaces dobles conjugados de silicio y silicio. Este estudio explora sus propiedades electrónicas únicas y modos de conjugación.

Área de la Ciencia:

Química del silicio orgánico
Ciencias de los materiales

Sus antecedentes:

Comprensión limitada de los modos de conjugación en los bis (disilenos).
Necesidad de sistemas conjugados estables basados en silicio.

Objetivo del estudio:

Informar sobre la síntesis y las propiedades de un nuevo pentasila-1,4-dieno.
Para investigar la conjugación electrónica entre los enlaces dobles silicio-silicio.

Principales métodos:

Reacción del disilenido con el diclorodimetilsilano.
Análisis espectroscópico del pentasila-1,4-dieno resultante.

Principales resultados:

Se ha logrado la síntesis de pentasila-1,4-dieno estable (1).
Se observó una ampliación y un desplazamiento hacia el rojo de la banda de absorción π ((SiSi) → π * ((SiSi) en comparación con los compuestos relacionados.
La banda de absorción está desplazada hacia el azul en relación con los tetrasila-1,3-dienes.

Conclusiones:

Los desplazamientos espectrales observados se atribuyen a la homoconjugación entre los enlaces dobles SiSi a través de la unidad SiMe2.
El pentasila-1,4-dieno exhibe propiedades electrónicas únicas debido a su vía de conjugación específica.

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