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Mejora del plegamiento helicoidal de los ortofenilenos mediante el control de las interacciones de apilamiento

Sanyo Mathew¹, Laura A Crandall, Christopher J Ziegler

¹Department of Chemistry & Biochemistry, Miami University , Oxford, Ohio 45056, United States.

Journal of the American Chemical Society

|November 7, 2014

Resumen

Se desarrollaron nuevos pliegues de ortofenileno con propiedades de plegado helicoidal mejoradas. Los sustituyentes que retiran electrones mejoran significativamente el sesgo conformacional, lo que lleva a estructuras altamente plegadas útiles en arquitecturas moleculares complejas.

Área de la Ciencia:

Química supramolecular de las moléculas.
La ciencia de los polímeros es la ciencia de los polímeros.
Química orgánica es la química orgánica.

Sus antecedentes:

Los ortofenilenos son foldámeros que utilizan el apilamiento aromático para la formación de hélices.
Los ortofenilenos existentes exhiben plegamiento moderado (50-75% conformador plegado).
El plegado mejorado es crucial para aplicaciones avanzadas en arquitecturas moleculares complejas.

Objetivo del estudio:

Diseñar y sintetizar nuevos oligómeros de ortofenileno con propiedades de plegado mejoradas.
Investigar el impacto de la naturaleza y orientación de los sustituyentes en el comportamiento conformacional.
Establecer directrices para evaluar el plegado de pliegues.

Principales métodos:

Síntesis de diversas series de oligómeros de ortofenileno.
Análisis de conformación mediante espectroscopia de resonancia magnética nuclear (RMN).
Modelado computacional con cálculos de la Teoría Funcional de la Densidad (DFT).
Elucidación estructural a través de la cristalografía de rayos X.

Principales resultados:

Los oligómeros con sustituyentes de retirada de electrones muestran un plegamiento significativamente mejorado.
Los oligómeros sustituidos por acetoxi logran >90% de conformidad plegada.
Los sustituyentes de triflato y ciano hacen que los estados mal plegados sean indetectables por RMN.
El plegado de Foldamer demuestra una débil dependencia del disolvente.

Conclusiones:

Los grupos de retirada de electrones son la clave para lograr foldameres de ortofenileno altamente plegados.
Estos foldamers de próxima generación ofrecen un control conformacional superior.
Los hallazgos proporcionan una base para la utilización de foldamers en materiales funcionales avanzados.

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