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Interruptores moleculares de 2,7- y 4,9-dialcinildihidropireno: síntesis, propiedades y transporte de carga en

Max Roemer¹, Angus Gillespie¹, David Jago¹

¹Chemistry, School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.

Journal of the American Chemical Society

|June 29, 2022

Resumen

Este estudio detalla la síntesis de interruptores moleculares funcionalizados de dihidropireno (DHP). Estos interruptores exhiben conmutación reversible y conductancia ajustable, allanando el camino para la electrónica molecular.

Área de la Ciencia:

Química orgánica
Ciencias de los materiales
La electrónica molecular

Sus antecedentes:

Los dihidropirenos funcionalizados (DHP) son interruptores moleculares prometedores.
El control de sus propiedades electrónicas es crucial para las aplicaciones.

Objetivo del estudio:

Para sintetizar nuevos DHP funcionalizados con diferentes patrones de sustitución.
Para investigar su comportamiento de conmutación y sus propiedades de transporte de carga.

Principales métodos:

Alquilación nucleofílica regioselectiva para la síntesis de DHP.
Cristalografía de rayos X para elucidación estructural.
Espectroelectroquímica, voltametría cíclica y irradiación luminosa para la evaluación de las propiedades.
Microscopía de túnel de barrido (STM) de las uniones de ruptura y cálculos DFT para el análisis del transporte de carga.

Principales resultados:

Síntesis exitosa de DHPs funcionalizados con 2,7-alquina y DHPs con grupos de anclaje superficial.
Se ha demostrado el cambio electroquímico reversible entre las formas de DHP y de ciclofanedieno (CPD).
Junciones moleculares estables formadas por DHPs con grupos en contacto con la superficie.
La conductividad molecular depende de los patrones de sustitución de DHP y disminuye con el aumento del sesgo.

Conclusiones:

Se sintetizaron y caracterizaron nuevos DHP funcionalizados.
Se confirmaron las propiedades reversibles de conmutación electroquímica y transporte de carga.
Los hallazgos apoyan el desarrollo de dispositivos electrónicos moleculares basados en DHP.

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