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Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
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El polimorfismo conformacional impulsado por aniones en polímeros de coordinación helicoidal homoquiral
Guozan Yuan1, Chengfeng Zhu, Yan Liu
1School of Chemistry and Chemical Technology and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China.
Journal of the American Chemical Society
|September 3, 2009
Resumen
Los investigadores crearon marcos quirales en 3D utilizando polímeros helicoidales y iones de plata. El tipo de anión dicta el plegamiento de la hélice y el ensamblaje en estructuras únicas, lo que demuestra un autoensamblaje dependiente de aniones.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
- Coordinación Química de la Coordinación
Sus antecedentes:
- Los marcos quirales 3D son esenciales para los materiales avanzados.
- El control del autoensamblaje de los ligandos y los iones metálicos es clave para el diseño del marco.
Objetivo del estudio:
- Para sintetizar nuevos marcos homoquirales en 3D.
- Para investigar el autoensamblaje dependiente de aniones de los ligandos quirales y los iones de plata.
- Comprender la relación entre las contraaniones y las estructuras marco resultantes.
Principales métodos:
- Síntesis de los ligandos 3,3'-bipiridina quirales y axiales.
- Coordinación con las agencias.
- Estudios de agregación de soluciones utilizando (1) RMN H, UV-vis, CD, GPC y MALDI-TOF.
- Análisis estructural de estado sólido de los marcos resultantes.
Principales resultados:
- Formación de tres marcos 3D homoquiral con distintas arquitecturas helicoidales.
- Polimorfismo conformacional dependiente de aniones: hélices de dos, tres y cuatro pliegues formadas con NO ((3) ((-), PF ((6) ((-), y ClO ((4) ((-), respectivamente.
- Las hélices dobles formaron hélices sextuples a través de interacciones Ag-Ag; las hélices triples y cuádruples formaron arquitecturas tubulares.
- Se ha demostrado un autoensamblaje dependiente de aniones impulsado por factores estéricos y electrónicos.
Conclusiones:
- El estudio reunió con éxito marcos 3D quirales que responden a los aniones.
- Las propiedades del contraanión influyen significativamente en la conformación helicoidal del polímero y en el ensamblaje supramolecular.
- Este trabajo proporciona información sobre el diseño de arquitecturas quirales complejas a través del autoensamblaje controlado.
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