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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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Caracterización dinámica de rotores supramoleculares cristalinos ensamblados a través de enlaces halógenos
Luca Catalano1,2, Salvador Pérez-Estrada2, Giancarlo Terraneo1
1Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering "Giulio Natta", Politecnico di Milano , via L. Mancinelli 7, 20131 Milano, Italy.
Journal of the American Chemical Society
|November 20, 2015
Resumen
Los investigadores desarrollaron un kit modular para crear rotores moleculares cristalinos. Estos rotores exhiben una rotación ultra rápida, lo que demuestra un nuevo método para diseñar materiales con propiedades ajustables.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- Química orgánica
Sus antecedentes:
- Los rotores moleculares son cruciales para el desarrollo de materiales avanzados con propiedades dinámicas sintonizables.
- Diseñar y sintetizar diversas estructuras de rotores moleculares puede ser un desafío.
- El autoensamblaje ofrece una ruta prometedora para la construcción de arquitecturas moleculares complejas.
Objetivo del estudio:
- Diseñar un kit molecular modular para la preparación de rotores moleculares cristalinos.
- Para lograr un acceso sencillo a una amplia gama de estructuras con variadas prestaciones dinámicas y propiedades físicas.
- Investigar la dinámica y los mecanismos de rotación de nuevos rotores moleculares autoensamblados.
Principales métodos:
- Utilizó un enfoque modular con diazabiciclo [2.2.2] octano como el rotador y cinco iodobenzenos sustituidos por flúor como el estator.
- Enlaces halógenos empleados para el autoensamblaje de rotores moleculares cristalinos.
- Se llevaron a cabo mediciones de relajación de la rejilla de giro a temperatura variable (1) H T1 para estudiar la dinámica de rotación.
- Se realizó un análisis de la forma de la línea de las mediciones de RMN de eco cuadrupolar (2) H para determinar las trayectorias de rotación.
Principales resultados:
- Sintetizó con éxito rotores moleculares cristalinos utilizando el kit modular y el enlace halógeno.
- Demostró una rotación browniana ultra rápida para todas las estructuras sintetizadas.
- Energías de activación determinadas que oscilan entre 2,4-4,9 kcal/mol y factores preexponenciales de (1-9) × 10(12) s(-1).
- Los datos de RMN indicaron trayectorias de rotación consistentes con potenciales simétricos de 3 o 6 veces.
Conclusiones:
- El kit modular proporciona un acceso directo a una biblioteca diversa de rotores moleculares cristalinos.
- Los rotores autoensamblados exhiben una dinámica de rotación eficiente y ultrarrápida.
- Este trabajo sienta las bases para diseñar máquinas y materiales moleculares con movimiento controlado con precisión.
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