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Síntesis en dos pasos de helicenos dobles fundidos con boro
Takazumi Katayama1, Soichiro Nakatsuka1, Hiroki Hirai1
1Department of Chemistry, School of Science and Technology, Kwansei Gakuin University , 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan.
Journal of the American Chemical Society
|April 15, 2016
Resumen
Se sintetizaron nuevos helicenos dobles [5] fusionados con boro, que exhiben una excelente conductividad ambipolar debido al apilamiento π 3D. Los grupos tert-butilo permitieron la resolución óptica, produciendo enantiómeros fluorescentes de color azul profundo con luminiscencia polarizada circularmente.
Área de la Ciencia:
- Química orgánica
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- Los helicenos son hidrocarburos aromáticos policíclicos quirales con estructuras tridimensionales únicas.
- El desarrollo de nuevos derivados de heliceno con propiedades electrónicas y ópticas adaptadas es crucial para los materiales avanzados.
- El control de la racemización y el logro de la pureza enantiomérica son desafíos clave en la química del heliceno.
Objetivo del estudio:
- Para sintetizar nuevos helicenos dobles [5] fusionados con boro.
- Investigar las propiedades electrónicas y ópticas de estos nuevos derivados de heliceno.
- Para explorar el impacto de la sustitución de tert-butilo en la estabilidad del heliceno y la resolución óptica.
Principales métodos:
- Síntesis en dos pasos que incluye la reacción de Hart y la ciclización desmetilativa a partir del hexabromobenzeno.
- Caracterización de helicenos dobles [5] sintetizados con boro mediante técnicas espectroscópicas y analíticas.
- Evaluación de la conductividad eléctrica y las propiedades fotofísicas, incluida la fluorescencia y la luminiscencia polarizada circularmente.
Principales resultados:
- Síntesis exitosa de nuevos helicenos dobles [5] fusionados con boro.
- El heliceno padre demostró una excelente conductividad ambipolar atribuida a un arreglo único de apilamiento π en 3D.
- La introducción de cuatro grupos tert-butilo suprimió efectivamente la racemización, facilitando la resolución óptica.
- El heliceno enantioméricamente puro exhibió fluorescencia azul profundo (coordenadas CIE (0.15, 0.08)) y demostró actividad de luminiscencia polarizada circularmente.
Conclusiones:
- La vía sintética desarrollada proporciona acceso a nuevos doble [5]helicenos fundidos con boro.
- Estos helicenos poseen una conductividad ambipolar prometedora y propiedades fotofísicas sintonizables.
- La estrategia de introducción del grupo tert-butilo es eficaz para permitir la resolución óptica y el acceso a materiales enantiopuros con aplicaciones potenciales en dispositivos quirópticos.
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