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Síntesis de circumpireno por alquino Benzanulación de dibenzo[hi],[st]ovaleno bromados

Qiang Chen¹, Dieter Schollmeyer², Klaus Müllen^1,3

¹Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 , Mainz , Germany.

Journal of the American Chemical Society

|December 10, 2019

Resumen

Los investigadores sintetizaron el circumpireno, un nanografeno complejo, utilizando la catálisis de metales de transición. Esta nueva molécula exhibe una estructura multizigzag única y propiedades electrónicas alteradas, allanando el camino para nuevos materiales.

Área de la Ciencia:

Química orgánica
Ciencias de los materiales
Nanotecnología

Sus antecedentes:

Los derivados del dibenzo[hi,st]ovaleno (DBOV) son hidrocarburos aromáticos policíclicos complejos.
La síntesis de nanografenos grandes y estructuralmente definidos sigue siendo un desafío.

Objetivo del estudio:

Desarrollar una nueva vía sintética para el circumpireno, un nanografeno con bordes en zigzag.
Investigar las propiedades estructurales y electrónicas del circumpireno sintetizado.

Principales métodos:

Reacción de bencanulación de alquino catalizada por metales de transición.
Caracterización mediante RMN, espectrometría de masas y difracción de rayos X de un solo cristal.
Análisis computacional que incluye el cálculo de la anisotropía de la densidad de corriente inducida (ACID).

Principales resultados:

Síntesis exitosa de circumpireno a partir de 3,11-dibromo-6,14-dimesetildibenzo[hi,st]ovaleno (DBOV).
El circumpireno posee una estructura de múltiples bordes en zigzag.
La introducción de nuevos enlaces CC aumentó significativamente las brechas de energía óptica y electroquímica en comparación con el DBOV.

Conclusiones:

La estrategia sintética desarrollada permite el acceso a nanografenes con bordes múltiples.
La estructura electrónica del circumpireno está modificada por su geometría única, mostrando un aumento de los sextetos de Clar y menos electrones π.
Este trabajo ofrece información sobre las relaciones estructura-propiedad de los nanografenos avanzados para potenciales aplicaciones optoelectrónicas.

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