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Oligo (perileno anulado por N) quinodimetanos: longitud de la cadena y estados del suelo dependientes del disolvente

Zebing Zeng^1,2, Sangsu Lee³, Minjung Son³

¹†Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.

Journal of the American Chemical Society

|June 12, 2015

Resumen

Se sintetizaron y estudiaron nuevos diradicaloides asimétricos. Sus propiedades dependen de la longitud de la cadena y el disolvente, ofreciendo información sobre el diseño molecular para aplicaciones de ciencia de materiales.

Área de la Ciencia:

Ciencia de los materiales Ciencia de los materiales.
Química orgánica es la química orgánica.
Química cuántica es la química cuántica.

Sus antecedentes:

Los diradicaloides singlet de cáscara abierta estables están ganando atención por sus propiedades y aplicaciones únicas.
La mayoría de los diradicaloides estudiados son simétricos; las variantes asimétricas con contribuciones zwitteriónicas son menos exploradas.

Objetivo del estudio:

Sintetizar e investigar nuevos perileno (quinodimetanos) asimétricos de empuje y tracción.
Estudie sistemáticamente la influencia de la longitud de la cadena y el disolvente en sus estados básicos y propiedades físicas.
Comprender las relaciones estructurales y de propiedades medioambientales fundamentales en estos nuevos sistemas asimétricos.

Principales métodos:

Síntesis de oligo ((N-anulado perileno) quinodimetanos de empuje y tracción.
Caracterización experimental que incluye la espectroscopia de absorción (estado estacionario, transitorio, de dos fotones), la cristalografía de rayos X, la resonancia de espín de electrones (ESR), el dispositivo de interferencia cuántica superconductor (SQUID), la espectroscopia Raman y la electroquímica.
Cálculos de la teoría funcional de la densidad (DFT) para el carácter diradical y el análisis de la carga de Hirshfeld.

Principales resultados:

La extensión de la longitud de la cadena aumenta el carácter diradical y disminuye la contribución zwitteriónica.
La transferencia de carga intramolecular conduce a propiedades físicas dependientes del disolvente.
Tanto los sistemas simétricos como los asimétricos exhiben longitud de cadena y dependencia del disolvente.

Conclusiones:

El estudio proporciona una comprensión completa de las relaciones estructura-propiedad en diradicaloides asimétricos.
Los hallazgos son cruciales para el diseño de nuevos materiales con propiedades ópticas, electrónicas y magnéticas personalizadas.
Esta investigación abre nuevas vías para el desarrollo de materiales orgánicos funcionales avanzados.

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