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Intercambio inducido por electrones de la quiralidad supramolecular de los agregados de politiofeno ópticamente
1Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan.
Journal of the American Chemical Society
|July 4, 2002
Resumen
Los agregados quirales de politiofeno exhiben una quiralidad supramolecular conmutable. La transferencia de electrones a través del dopaje / desdopaje con sales de cobre y aminas controla de manera reversible las señales de dicroísmo circular inducido (ICD).
Área de la Ciencia:
- Química supramolecular de las moléculas.
- La ciencia de los polímeros es la ciencia de los polímeros.
- Electrónica orgánica y electrónica orgánica.
Sus antecedentes:
- Los politiofenos regiorregulares quirales (PTs) forman agregados supramoleculares con dicroísmo circular inducido (ICD).
- Estos agregados quirales exhiben ICD en la región de transición pi-pi, influenciados por disolventes y sales metálicas.
Objetivo del estudio:
- Para demostrar el control reversible de la quiralidad supramolecular en agregados de politiofeno.
- Investigar el mecanismo de la conmutación de la quiralidad a través de la transferencia de electrones.
Principales métodos:
- Las espectroscopias de absorción y dicroísmo circular (CD) son espectroscopias de absorción y dicroísmo circular.
- Resonancia de espín de electrones (ESR, por sus siglas en inglés)
- Voltametría cíclica de voltaje.
- Difracción de rayos X por difracción de rayos X.
- Microscopía de fuerza atómica (AFM)
Principales resultados:
- La adición de cobre (II) trifluorometanosulfonato (Cu (OTf) 2) causó un dopaje oxidativo, lo que condujo a la desaparición del CDI.
- La adición posterior de trietilenetetramina (TETA) indujo el desdopaje, lo que resultó en la reaparición de ICD.
- La quiralidad supramolecular se encendió y apagó de manera reversible mediante el control de la transferencia de electrones en la cadena principal poli-1.
Conclusiones:
- Este estudio presenta el primer ejemplo de un interruptor de quiralidad supramolecular reversible en agregados quirales de politiofeno.
- El control reversible de la quiralidad se logra a través de procesos de dopaje y desdopaje en la columna vertebral del polímero.
- Los hallazgos abren caminos para el desarrollo de nuevos materiales para la electrónica quiral y sensores.
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