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Enlace B-N-B Fenalenilo Embebido y sus aniones
Haipeng Wei1, Yulan Liu1, Tullimilli Y Gopalakrishna2
1State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha 410082, People's Republic of China.
Journal of the American Chemical Society
|October 14, 2017
Resumen
Este estudio introduce nuevos fenalenilos integrados en boro-nitrógeno-boro (B-N-B) y sus formas aniónicas. Estos compuestos exhiben estructuras electrónicas y reactividad únicas, expandiendo las posibilidades en la optoelectrónica orgánica.
Área de la Ciencia:
- Química orgánica
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- Los hidrocarburos aromáticos policíclicos (HAP) que contienen heteroátomos son prometedores en la optoelectrónica orgánica.
- Existen investigaciones limitadas sobre los heteroaromáticos que presentan un enlace boro-nitrógeno-boro (B-N-B) dentro de su andamio π.
Objetivo del estudio:
- Sintetizar y caracterizar los nuevos derivados de 1,9-dibora-9a-azafenil (DBAP), conocidos como fenilenilos incrustados en BNB.
- Investigar la estructura electrónica y la reactividad de estos nuevos compuestos y sus especies aniónicas.
- Explorar las relaciones isoelectrónicas entre los derivados de DBAP y los cationes, aniones y radicales de fenalenilo.
Principales métodos:
- Reducción química de los derivados del DBAP mediante el uso de potasio.
- Análisis cristalográfico de rayos X para determinar las estructuras moleculares.
- Cálculos teóricos para comprender las propiedades electrónicas y la deslocalización.
- Análisis espectroscópico para la caracterización.
Principales resultados:
- Se sintetizaron derivados de fenalenilo (DBAP) estables incrustados en BNB.
- La reducción química produjo un dianión (14 π-electrones) isoelectrónico al anión fenalenilo.
- Una reorganización inusual produjo un dianión de benzo[cd]fluoranteno (20 π-electrones) incrustado en el BNB del monoanión, confirmado por la cristalografía de rayos X.
- La fracción B-N-B participa en la deslocalización de electrones π, aunque con un carácter más localizado en comparación con los análogos de todo carbono.
Conclusiones:
- Este trabajo informa de la primera síntesis y caracterización de fenalenilos incrustados en BNB y sus especies aniónicas.
- Estos compuestos exhiben estructuras electrónicas únicas y una reactividad distinta de los fenalenilos tradicionales.
- Los resultados abren nuevas vías para el diseño de materiales avanzados para la optoelectrónica orgánica.
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