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Metamorfosis isomérica: Si3E (E = S, Se y Te) biciclo[1.1.0]butano y ciclobuteno
Vladimir Ya Lee1, Shogo Miyazaki, Hiroyuki Yasuda
1Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan.
Journal of the American Chemical Society
|February 12, 2008
Resumen
Los investigadores sintetizaron nuevos butanos pesados biciclo[1.1.0] que contienen silicio y calcógenos. La fotólisis de estos compuestos produjo isómeros únicos de ciclobuteno, revelando información sobre sus mecanismos de unión y reacción.
Área de la Ciencia:
- Química del organosilicio Química del organosilicio
- Grupo Principal Química.
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- Los compuestos orgánicos de silicio con estructuras únicas son cruciales para la ciencia de los materiales.
- Comprender la reactividad y la unión en los anillos basados en silicio es un desafío continuo.
- Los calcógenos pesados (azufre, selenio, telurio) introducen nuevas propiedades electrónicas.
Objetivo del estudio:
- Para sintetizar y caracterizar el nuevo biciclo pesado [1.1.0]butanos.
- Para investigar el comportamiento fotolítico y la isomerización de estos compuestos.
- Para dilucidar las características de unión y los mecanismos de reacción involucrados.
Principales métodos:
- [1 + 2] Reacción de cicloadición entre el trisilireno y los calcógenos.
- Fotólisis de los derivados del biciclo[1.1.0]butano. fotólisis de los derivados del biciclo[1.1.0]butano.
- Estudios de etiquetado de deuterio para sondear los mecanismos de reacción.
- Cristalografía de rayos X para la determinación estructural.
Principales resultados:
- Síntesis exitosa de híbridos pesados de biciclo[1.1.0]butanos (Si3E, E = S, Se, Te).
- Observación de enlaces Si-Si de puente excepcionalmente cortos atribuidos al carácter del complejo pi.
- Transformación fotoquímica a ciclobutenos pesados planos (anillos de Si3E).
- Los estudios mecanicistas confirmaron una vía de isomerización directa y concertada.
Conclusiones:
- Los biciclo[1.1.0]butanos sintetizados exhiben un enlace único debido a la contribución del complejo pi de trisilireno-calcógeno.
- La fotólisis proporciona una ruta a nuevos isómeros de valencia pesados de ciclobuteno.
- La isomerización procede a través de un mecanismo concertado permitido por la simetría.
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