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La ruta de la base de Schiff hacia los pseudo-trifenilenos apilables: control estereoelectrónico del montaje y la
Justin A Riddle1, Stephen P Lathrop, John C Bollinger
1Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA.
Journal of the American Chemical Society
|August 24, 2006
Resumen
Los investigadores crearon nuevas moléculas discóticas utilizando el tándem tautomerización-atrapamiento. Estas moléculas se autoensamblan en columnas o cápsulas, mejorando la fluorescencia tras la agregación.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Materiales orgánicos Ciencia de la materia orgánica.
- La fotofísica es la fotofísica.
Sus antecedentes:
- Las moléculas discóticas son esenciales para el autoensamblaje y los materiales avanzados.
- Los derivados del trifenileno son sistemas discóticos bien estudiados.
- El control del autoensamblaje molecular es clave para ajustar las propiedades de los materiales.
Objetivo del estudio:
- Para sintetizar una nueva clase de moléculas discóticas análogas a los trifenilenos trisubstituidos.
- Para investigar el comportamiento de autoensamblaje de estas nuevas moléculas.
- Explorar el impacto de la geometría molecular en las propiedades fotofísicas, específicamente la fluorescencia.
Principales métodos:
- Reacciones de captura de tautomerización en tándem para sintetizar tris (N-salicilideneamina) s.
- Dispersión dinámica de la luz (DLS) para estudiar la agregación en solución.
- Espectroscopia de fluorescencia para medir las propiedades de emisión.
Principales resultados:
- Se sintetizó con éxito una nueva clase de moléculas discoticas con simetría C3.
- Estas moléculas se autoensamblan en columnas unidimensionales o cápsulas diméricas discretas a través de apilamiento cofacial pi-face.
- Se observó una mejora significativa de la fluorescencia tras la agregación molecular debido al refuerzo estructural.
Conclusiones:
- La tautomerización-atrapamiento en tándem es un método eficaz para acceder a nuevas arquitecturas discoticas.
- La simetría C3 y la complementariedad de formas impulsan la formación de estructuras supramoleculares ordenadas.
- La mejora de la fluorescencia inducida por autoensamblaje demuestra un potencial para aplicaciones en sensores u optoelectrónica.
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