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Las cadenas lineales flexibles actúan como baffles para inhibir la rotación intramolecular de los torniquetes
Chengyuan Yu1, Lishuang Ma1, Jiaojiao He1
1Key Laboratory of Theoretical and Computational Photochemistry and Key Laboratory of Radiopharmaceuticals, Ministry of Education; College of Chemistry, Beijing Normal University , Beijing 100875, China.
Journal of the American Chemical Society
|December 15, 2016
Resumen
Las cadenas flexibles en dispositivos moleculares pueden controlar el movimiento molecular. Los sustituyentes largos en los torniquetes moleculares actúan como deflectores, inhibiendo la rotación a altas velocidades pero permitiéndola a bajas velocidades, permitiendo nuevas funciones de la máquina molecular.
Área de la Ciencia:
- Máquinas moleculares
- Química supramolecular
- Nanotecnología
Sus antecedentes:
- Las cadenas flexibles en dispositivos moleculares artificiales generalmente muestran un control limitado sobre el movimiento molecular.
- Comprender la dinámica de los componentes moleculares es crucial para diseñar máquinas moleculares avanzadas.
Objetivo del estudio:
- Investigar las propiedades dinámicas de los torniquetes moleculares con sustituyentes flexibles.
- Establecer una correlación entre el obstáculo estérico y la velocidad de movimiento en cadenas flexibles dentro de dispositivos moleculares.
Principales métodos:
- Síntesis de torniquetes moleculares con un marco rígido y un rotador de fenilo.
- Incorporación de sustituyentes alcoximetílicos lineales de diferentes longitudes.
- Análisis de las propiedades dinámicas mediante espectroscopia de resonancia magnética nuclear (RMN) en la escala de tiempo de la RMN.
Principales resultados:
- Los sustituyentes flexibles actúan como deflectores elásticos, inhibiendo efectivamente el movimiento del rotador a velocidades medianas y rápidas.
- A velocidades de rotación más lentas, los sustituyentes se relajan, permitiendo el paso completo a través de la cavidad del torniquete.
- Se identificó una correlación entre el obstáculo estérico y la velocidad de movimiento de las cadenas flexibles.
Conclusiones:
- Las cadenas lineales flexibles se pueden diseñar para controlar el movimiento molecular en dispositivos artificiales.
- El comportamiento dinámico de los sustituyentes depende de la velocidad del rotador molecular.
- Este trabajo proporciona una base para el desarrollo de máquinas moleculares con sofisticados controles y funciones dinámicas.
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