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Realización de un interruptor molecular "bloqueable" a través de ciclizaciones moduladas por pH y redox

Craig J Richmond¹, Alexis D C Parenty, Yu-Fei Song

¹WestCHEM, Department of Chemistry, University of Glasgow, Glasgow G12 8QQ, United Kingdom.

Journal of the American Chemical Society

|September 4, 2008

Resumen

Los investigadores desarrollaron un sistema orgánico conmutable con cuatro estados controlados por el pH y la química redox. Este sistema permite cambios de estado reversibles y puede ser bloqueado en formas específicas, ofreciendo nuevas posibilidades en la conmutación molecular.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química supramolecular de las moléculas.
Interruptores moleculares Los interruptores moleculares son los interruptores moleculares que se encuentran en el interior de las moléculas.

Sus antecedentes:

El desarrollo de sistemas moleculares con múltiples estados controlables es crucial para aplicaciones avanzadas.
Los estímulos de pH y redox ofrecen mecanismos de control ortogonales para dispositivos moleculares.

Objetivo del estudio:

Diseñar y caracterizar un nuevo sistema orgánico conmutable con cuatro estados interconvertibles.
Investigar el uso del pH y la química redox para controlar los estados moleculares.

Principales métodos:

Síntesis de heterociclos basados en la fenantridina: 1-isobutilo-1,2,3,12b-tetrahidroimidazo[1,2-f]fenantridina (TIP) y 5-[2-(isobutilamino) etil]fenantridinio (AEP).
Determinación de la estructura in situ mediante espectroscopia UV y 1H NMR en una solución bifásica DCM/agua.
Aplicación de estímulos de pH y redox para inducir interconversiones de estados.

Principales resultados:

Desarrolló con éxito un sistema orgánico conmutable de cuatro estados.
Se ha demostrado la interconversión reversible entre los estados TIP y AEP a través del control del pH.
Se logra la conversión a estados pH-inertes (DIP y AEDP) a través de la oxidación o reducción.
Procesos de ciclización y transferencia de fase con pH modulado confirmados, cuantitativos y repetibles.
Mostró la capacidad de bloquear los estados contra los cambios ácido-base utilizando la manipulación redox.

Conclusiones:

El sistema desarrollado ofrece un control robusto y repetible sobre los estados moleculares utilizando estímulos ortogonales de pH y redox.
La capacidad de bloquear estados proporciona un mecanismo para la memoria en los sistemas moleculares.
Este trabajo sienta las bases para el diseño de sofisticadas máquinas moleculares y materiales sensibles.

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