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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
La estabilización intramolecular de halógenos de iones de silicio dirige la dinámica de engranajes
Paola Romanato1, Simon Duttwyler, Anthony Linden
1Organic Chemistry Institute, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
Journal of the American Chemical Society
|May 27, 2010
Resumen
El estudio revela el intercambio dinámico de flúor en un catión silílico a través de un mecanismo de engranajes disrotatorios. Esto contrasta con el proceso conrotatorio observado para su análogo de cloro, destacando el papel de los halógenos en la dinámica química.
Área de la Ciencia:
- Química del organosilicio Química del organosilicio
- Química computacional es la química computacional.
- Mecanismos de reacción Mecanismos de reacción
Sus antecedentes:
- Los cationes silílicos pentavalentes exhiben geometrías y reactividad únicas.
- La coordinación de halógenos influye en el comportamiento dinámico de los centros de silicio.
Objetivo del estudio:
- Para aclarar el mecanismo de intercambio de halógenos en el ion 2,6-Bis(2,6-difluorofenil) fenilidimetilesilanio.
- Para comparar los procesos dinámicos de intercambio de flúor y cloro en un centro de silicio.
Principales métodos:
- Modelado computacional de la geometría molecular y los estados de transición.
- Análisis de procesos dinámicos utilizando descriptores estereoquímicos.
Principales resultados:
- El derivado del flúor (1a) adopta una geometría trigonal-bipiramidal con coordinación ápica del flúor.
- El intercambio de flúor se produce a través de un mecanismo de engranajes disrotatorios con un estado de transición simétrico C (((s).
- El análogo del cloro (1b) exhibe un mecanismo de intercambio conrotatorio.
Conclusiones:
- El comportamiento dinámico de los cationes silílicos pentavalentes depende de la naturaleza del halógeno coordinador.
- Las vías estereoquímicas para el intercambio de halógenos difieren significativamente entre el flúor y el cloro.
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