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Superar las reacciones de reordenamiento inducidas por la tensión: un protocolo de aromatización deshidratante leve

Nirmal K Mitra¹, Rolande Meudom¹, Hector H Corzo¹

¹Department of Chemistry and Biochemistry, Auburn University , Auburn, Alabama 36849, United States.

Journal of the American Chemical Society

|February 12, 2016

Resumen

Los investigadores sintetizaron macrociclos de p-terfenilo tensados utilizando un protocolo simplificado. Un nuevo método de reactivos Burgess evita el reordenamiento, lo que produce unidades aromáticas altamente distorsionadas.

Área de la Ciencia:

Química orgánica
Química supramolecular

Sus antecedentes:

Los compuestos macrocíclicos son cruciales en la química supramolecular.
La síntesis de sistemas aromáticos de alta tensión presenta desafíos significativos.

Objetivo del estudio:

Desarrollar una síntesis simplificada para los macrociclos basados en p-terfenilo.
Para crear unidades de p-fenileno muy distorsionadas dentro de estructuras macrocíclicas.
Para superar los problemas de reordenamiento durante la aromatización deshidratante.

Principales métodos:

Síntesis de macrociclos basados en p-terfenilo mediante el uso de 1,4-diketonas.
Utilizando el catalizador de segunda generación de Hoveyda-Grubbs para la metátesis y la hidrogenación de transferencia.
Empleando un protocolo de deshidratación por medio de un reactivo Burgess.

Principales resultados:

Síntesis exitosa de macrociclos de p-terfenilo no planos sin catálisis de Pd o Ni.
Desarrollo de un protocolo simplificado utilizando sólo un catalizador de 2,5 mol por ciento.
Obtención de unidades de p-fenileno de alta tensión (hasta 28,4 kcal/mol de energía de tensión) sin reordenamiento.

Conclusiones:

El protocolo desarrollado ofrece una ruta eficiente a los sistemas aromáticos macrocíclicos tensados.
El método de reactivos de Burgess evita efectivamente las reorganizaciones inducidas por la tensión.
Este trabajo permite el acceso a nuevos bloques de construcción aromáticos distorsionados para materiales avanzados.

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