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Cambio de quiralidad unimolecular acido/base de un pilar[5] azacoroa pseudo[1] Catena

Haozhong Liang¹, Bin Hua¹, Fan Xu²

¹State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China.

Journal of the American Chemical Society

|November 6, 2020

Resumen

Este estudio introduce un nuevo sistema de conmutación ácido/base para el cambio de quiralidad unimolecular en pseudo[1]catenanas. La protonación y la desprotonación controlan de manera reversible la estructura molecular y las propiedades quirópticas.

Área de la Ciencia:

Química supramolecular
Química orgánica
Ciencias de los materiales

Sus antecedentes:

Los sistemas moleculares que responden a los estímulos ofrecen un control simultáneo de la estructura y la función.
El cambio de quiralidad unimolecular es crucial para el desarrollo de dispositivos moleculares dinámicos.
La química macrocíclica proporciona una plataforma versátil para el diseño de arquitecturas moleculares complejas.

Objetivo del estudio:

Desarrollar un nuevo sistema de conmutación de quiralidad unimolecular sintonizable ácido/base.
Para investigar los cambios conformacionales reversibles y las inversiones quirópticas en un pseudo[1]catenano basado en pillarareno.
Explorar el potencial de los sistemas macrocíclicos en la química de la quiralidad supramolecular.

Principales métodos:

Síntesis de un pilar cíclico[5] y pseudo[1]catenano (PN4).
Utilizando la titulación ácido/base para inducir la protonación y la desprotonación.
Caracterización mediante espectroscopia de resonancia magnética nuclear (RMN), espectroscopia de dicroísmo circular (CD) y difracción de rayos X de un solo cristal.

Principales resultados:

El pseudo[1]catenano sintetizado PN4 exhibe transformaciones conformacionales reversibles entre los estados de autoinclusión y autoexclusión.
Los estímulos ácido/base inducen inversiones quirópticas significativas, lo que demuestra un cambio de quiralidad efectivo.
El análisis estructural confirma la regulación de la conformación molecular mediada por ácido/base.

Conclusiones:

Se ha desarrollado con éxito un nuevo sistema pseudo[1]catenano basado en pillarareno capaz de cambiar la quiralidad unimolecular sensible a estímulos.
Este sistema demuestra un nuevo paradigma para el control de la quiralidad supramolecular en la química macrocíclica.
Los hallazgos abren nuevas vías para diseñar materiales moleculares funcionales avanzados.

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