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Oligoelementos de escalera ((p-fenilenovileno) con puentes de silicio y carbono
Caihong Xu1, Atsushi Wakamiya, Shigehiro Yamaguchi
1Department of Chemistry, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
Journal of the American Chemical Society
|February 11, 2005
Resumen
Los investigadores han desarrollado un método versátil para sintetizar oligo-p-fenileno-vinileno de escalera (LOPV) con puentes de silicio y carbono. Esta técnica crea sistemas pi-conjugados extendidos y planos que exhiben fluorescencia brillante y pequeños desplazamientos de Stokes.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Ciencia de los materiales Ciencia de los materiales.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Los oligo ((p-fenilenovinileno) de escalera (LOPV) son sistemas pi-conjugados cruciales con aplicaciones potenciales en la electrónica orgánica.
- Los métodos sintéticos existentes a menudo carecen de versatilidad o luchan por producir estructuras de escalera extendidas y bien definidas.
Objetivo del estudio:
- Desarrollar una metodología sintética general y versátil para la construcción de oligo-p-fenileno-vinileno (LOPV) de escalera y sistemas pi-electrónicos relacionados.
- Para permitir la síntesis de una serie homóloga de LOPV con diferentes grados de fusión de anillos.
- Caracterizar las propiedades estructurales y fotofísicas de los sistemas de escaleras sintetizadas.
Principales métodos:
- Una nueva estrategia sintética que combina la ciclización reductora intramolecular de los derivados de (o-sililfenilo) acetileno y la ciclización tipo Friedel-Crafts.
- Aplicación secuencial de estas reacciones de ciclización para construir el sistema de anillos fundidos.
- Análisis estructural de cristal y mediciones fotofísicas (espectroscopia de fluorescencia) para caracterizar los productos.
Principales resultados:
- Síntesis exitosa de una serie homóloga de LOPV, incluido un sistema de fusión de 13 anillos.
- El análisis de la estructura cristalina reveló un marco pi-conjugado casi plano (aprox. 2.9 nm de longitud) para el LOPV. más grande.
- Todos los sistemas de pi-electrones de escalera sintetizados mostraron una fluorescencia visible intensa con altos rendimientos cuánticos y pequeños desplazamientos de Stokes.
Conclusiones:
- El método sintético desarrollado es general y versátil para crear complejos sistemas pi-conjugados de escalera.
- Los LOPV sintetizados poseen propiedades fotofísicas deseables, incluida una fuerte fluorescencia y un desplazamiento mínimo de Stokes, lo que los hace prometedores para aplicaciones optoelectrónicas.
- Este trabajo amplía el alcance de los materiales pi-conjugados accesibles con características electrónicas y ópticas sintonizables.
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