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Los nanógrafos 3D moleculares Homo y Hetero emplean un andamio de cicloctatetraeno
Javier Urieta-Mora1,2, Marcel Krug3, Wiebke Alex3
1Departamento Química Orgánica, Facultad C. C. Químicas, Universidad Complutense de Madrid, Av. Complutense s/n, 28040 Madrid, Spain.
Journal of the American Chemical Society
|December 21, 2019
Resumen
Los investigadores diseñaron nuevos nanógrafos 3D (NG1, NG2) con un núcleo de ciclooctatetraeno. Estas estructuras estables ricas en electrones fueron sintetizadas utilizando un enfoque de abajo hacia arriba y caracterizadas por cristalografía de rayos X.
Área de la Ciencia:
- Química orgánica
- Ciencias de los materiales
- Nanotecnología
Sus antecedentes:
- El desarrollo de nuevos nanomateriales basados en carbono es crucial para aplicaciones avanzadas.
- Los nanógrafos tridimensionales ofrecen propiedades electrónicas y estructurales únicas.
- La síntesis eficiente de hidrocarburos aromáticos policíclicos complejos sigue siendo un reto.
Objetivo del estudio:
- Diseñar y sintetizar nuevos nanografenos tridimensionales (NG1 y NG2) con un núcleo de ciclooctatetraeno.
- Caracterizar la estructura, las propiedades y la estabilidad de los nanografenos sintetizados.
- Investigar fenómenos de estado excitado, incluida la transferencia de electrones y energía.
Principales métodos:
- Una metodología sintética concisa y eficiente de abajo hacia arriba.
- Formación de 24 nuevos enlaces carbono-carbono.
- Reacción de Scholl para la ciclización para formar 53 anillos fundidos.
- Cristalografía de rayos X de un solo cristal para elucidación estructural.
- Pruebas de solubilidad en disolventes orgánicos comunes.
- Investigaciones de estado excitado (transferencia de electrones y energía).
Principales resultados:
- Síntesis y caracterización exitosas de dos nuevos nanografenos 3D (NG1 y NG2).
- Se logra una buena solubilidad en disolventes orgánicos comunes.
- Estructuras ricas en electrones con buena estabilidad química y electroquímica.
- Confirmado la quiralidad y la cristalización racémica a través de la cristalografía de rayos X.
- Capacidad demostrada de transferencia de electrones y energía.
Conclusiones:
- Se sintetizaron y caracterizaron con éxito nuevos nanografenos 3D con un núcleo de ciclooctatetraeno.
- Los nanographenes sintetizados exhiben propiedades deseables como buena solubilidad, estabilidad y naturaleza rica en electrones.
- El análisis estructural reveló moléculas quirales parecidas a sillas de montar que se cristalizan como mezclas racémicas.
- El estudio proporciona una base para explorar las propiedades fotofísicas y las aplicaciones potenciales de estos nanografenos.
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