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Bis ((9-Borafenantreno) y su radical estable
Samir Kumar Sarkar1, Kimberly K Hollister1, Andrew Molino2
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|September 22, 2023
Resumen
Los investigadores desarrollaron nuevos hidrocarburos aromáticos policíclicos dopados con boro con propiedades electrónicas y fotofísicas únicas. Crearon los primeros compuestos neutrales bis ((9-borafenantreno) y un raro biradical, mostrando nuevas posibilidades en la ciencia de los materiales.
Área de la Ciencia:
- Química orgánica
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- Los hidrocarburos aromáticos policíclicos dopantes de boro (HAP) ofrecen propiedades redox y fotofísicas únicas que no se encuentran en los sistemas basados únicamente en carbono.
- El control de los estados electrónicos en estos marcos dopados con boro es crucial para el desarrollo de materiales avanzados.
Objetivo del estudio:
- Para lograr un control mediado por ligandos sobre los estados electrónicos de los sistemas de 9-borafenantreno.
- Para sintetizar y caracterizar los compuestos neutrales bis ((9-boraphenanthrene) y sus biradicales correspondientes.
- Investigar las propiedades fotofísicas, incluida la transferencia de carga intramolecular y la doble emisión.
Principales métodos:
- Síntesis mediada por ligandos de HAP dopados con boro.
- Caracterización estructural mediante técnicas espectroscópicas avanzadas.
- Mediciones fotofísicas para determinar las propiedades de absorción y emisión.
Principales resultados:
- Primeros compuestos neutros (2-3) y sus birádicos (4) caracterizados estructuralmente.
- Los compuestos 2 y 3 presentan transferencia de carga intramolecular y doble emisión en solución debido a la mejora de la conjugación en estado excitado (ESCE).
- Biradical 4 es un singular raro de cáscara abierta con un 95% de carácter biradical, uno de los más altos para las especies policíclicas a base de boro.
Conclusiones:
- El control de ligandos permite el acceso a diversos estados electrónicos en los HAP dopados con boro.
- Estos nuevos compuestos demuestran comportamientos fotofísicos únicos, incluida la doble emisión.
- El compuesto altamente biradical abre nuevas vías para la química radical y las aplicaciones de materiales.
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