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Nanografías moleculares quirales con arreglo helicoidal
Patricia Izquierdo-García1, Jesús M Fernández-García1, Israel Fernández1
1Departamento de Química Orgánica I, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain.
Journal of the American Chemical Society
|July 20, 2021
Resumen
Los investigadores sintetizaron nanografenos moleculares quirales con una estructura helicoidal. Estos compuestos, con unidades de dibenzo[fg,ij]fenantro[9,10,1,2,3-pqrst]pentafeno (DBPP), forman mezclas racémicas que pueden resolverse y exhibir propiedades electroquímicas y fluorescentes interesantes.
Área de la Ciencia:
- Química orgánica
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- El desarrollo de nuevas estructuras de nanografeno con propiedades únicas es crucial para los materiales avanzados.
- La exploración de la quiralidad en las arquitecturas moleculares puede conducir a nuevas aplicaciones en óptica y electrónica.
Objetivo del estudio:
- Sintetizar y caracterizar nuevos nanografenos moleculares con una disposición helicoidal definida.
- Investigar la quiralidad, la resolución y las propiedades de estas nuevas estructuras de nanografeno.
Principales métodos:
- Síntesis en fase de solución de las unidades de nanografeno vinculadas covalentemente.
- Difracción de rayos X para el análisis de la estructura cristalina.
- Cromatografía líquida quiral de alto rendimiento (HPLC) para la resolución de enantiómeros.
- Resonancia magnética nuclear de protones (1H NMR) para el estudio de la isomerización rotacional.
- Mediciones electroquímicas y fotofísicas.
Principales resultados:
- Síntesis exitosa de nanografenos moleculares que comprenden dos fracciones ortogonales de dibenzo[fg,ij]fenantro[9,10,1,2,3-pqrst]pentafeno (DBPP) unidas por un anillo de tetrafluorobenzeno.
- Demostración de un eje quiral debido a la disposición helicoidal, lo que resulta en una mezcla racémica.
- Co-cristalización de ambos enantiómeros observados a través de la difracción de rayos X.
- Resolución exitosa de la mezcla racémica mediante HPLC quiral.
- Observación de la isomerización rotacional en los diastereoisómeros a través de la RMN de 1H.
- Caracterización de las propiedades electroactivas y fluorescentes.
Conclusiones:
- El estudio presenta una nueva ruta sintética para los nanógrafos moleculares quirales y helicoidales.
- Los compuestos sintetizados exhiben propiedades susceptibles de separación y caracterización, incluida la quiralidad y la fluorescencia.
- Estos hallazgos abren caminos para el diseño de nuevos materiales orgánicos funcionales con características optoelectrónicas adaptadas.
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