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Síntesis de flujo de alto rendimiento de una bisagra molecular macrocíclica

Christopher D Jones¹, Laurence J Kershaw Cook¹, David Marquez-Gamez¹

¹Department of Chemistry and Materials Innovation Factory, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K.

Journal of the American Chemical Society

|May 7, 2021

Resumen

Los investigadores desarrollaron nuevas bisagras moleculares parecidas a pinzas a partir de macrociclos isoméricos. Estos componentes químicos versátiles permiten nuevas posibilidades para receptores supramoleculares adaptativos y materiales porosos flexibles.

Área de la Ciencia:

Química supramolecular
Síntesis orgánica
Ciencias de los materiales

Sus antecedentes:

Las máquinas moleculares a menudo utilizan componentes modulares como ejes y ruedas.
Las bisagras moleculares existentes se basan principalmente en rotaciones diédricas, no en mecanismos parecidos a pinzas.
Hay una necesidad de bisagras moleculares que imiten dispositivos con bisagras macroscópicas.

Objetivo del estudio:

Diseñar y sintetizar nuevos compuestos macrocíclicos que funcionan como bisagras moleculares parecidas a las abrazaderas.
Desarrollar una ruta sintética escalable y eficiente para estos macrociclos.
Explorar las aplicaciones potenciales de estas bisagras moleculares en materiales avanzados.

Principales métodos:

Síntesis de dos macrociclos isoméricos a través de una reacción de ciclización de adición de un solo recipiente.
Caracterización de las estructuras del macrociclo y el comportamiento conformacional utilizando espectroscopia de RMN.
Desarrollo de una síntesis de flujo semicontinuo optimizada para el rendimiento y la selectividad.
Investigación de las propiedades de encapsulación del huésped y de la inercia química.

Principales resultados:

Se sintetizaron dos macrociclos isoméricos con geometrías abiertas y cerradas distintas.
Los macrociclos se interconvierten libremente en solución y se pueden producir en una escala multigramada de manera eficiente.
Una síntesis de flujo semicontinuo logró altas conversiones (85-93%) y selectividad (>80%).
Los macrociclos poseen huecos estéricamente protegidos, lo que demuestra su inercia a las especies reactivas como los iones fluoruro.

Conclusiones:

Los macrociclos sintetizados representan una nueva clase de bisagras moleculares con una funcionalidad similar a la de las pinzas.
La síntesis eficiente y escalable facilita su uso en la construcción de sistemas moleculares complejos.
Estas bisagras químicamente inertes son bloques de construcción prometedores para receptores supramoleculares adaptativos y materiales porosos flexibles.

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