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Polímeros quirales de coordinación enantioméricamente puros: síntesis, espectroscopia y electroquímica en solución y
S Bernhard1, K Takada, D J Díaz
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
Journal of the American Chemical Society
|October 18, 2001
Resumen
Los polímeros de coordinación quiral con hasta 60 unidades repetitivas fueron sintetizados utilizando reacciones estereospecíficas y hierro (II). El dicroísmo circular y las imágenes de STM confirmaron sus estructuras helicoidales y su alto orden, con propiedades electroquímicas similares a los complejos monoméricos.
Área de la Ciencia:
- Coordinación Química de la Coordinación
- La ciencia de los polímeros es la ciencia de los polímeros.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Los ligandos quirales de tipo terpiridil son bloques de construcción para arquitecturas complejas.
- La síntesis estereospecífica es crucial para controlar la quiralidad del polímero.
- Los complejos de hierro (II) ofrecen propiedades redox sintonizables.
Objetivo del estudio:
- Para sintetizar polímeros quirales de coordinación enantioméricamente puros.
- Para caracterizar la estructura y la helicidad de los polímeros.
- Para investigar el comportamiento electroquímico de los polímeros quirales redox.
Principales métodos:
- Alquilación estereospecífica para la síntesis de ligandos.
- Espectrofotometría para el monitoreo de la reacción.
- Dicroísmo circular e imágenes STM para el análisis estructural.
- Voltametría cíclica para estudios electroquímicos.
Principales resultados:
- Se prepararon con éxito ligandos puentes enantioméricamente puros y polímeros de coordinación quiral.
- Se formaron dominios poliméricos helicoidales de alto orden con hasta 60 unidades en sustratos HOPG.
- El dicroísmo circular confirmó la configuración absoluta de las estructuras helicoidales.
- Las propiedades electroquímicas de los polímeros fueron comparables a los complejos monoméricos, con un comportamiento de centro metálico independiente.
Conclusiones:
- El estudio demuestra la síntesis exitosa de polímeros de coordinación quiral altamente ordenados, enantioméricamente puros.
- Los hallazgos destacan el potencial de estos materiales en áreas que requieren reconocimiento quiral y actividad redox.
- El comportamiento independiente de los centros metálicos sugiere aplicaciones en la electrónica molecular.
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