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Updated: Jul 23, 2025

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Reacciones asimétricas catalíticas de Friedel-Crafts de arenas no activadas

Sebastian Brunen¹, Benjamin Mitschke¹, Markus Leutzsch¹

¹Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany.

Journal of the American Chemical Society

|July 13, 2023

Resumen

Este estudio introduce una nueva reacción asimétrica de Friedel-Crafts para arenas no activadas, lo que permite la síntesis de ésteres de arilglicina enriquecidos con enantio. Este avance amplía el alcance de la catálisis asimétrica para los alquilbenzenos simples.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

La reacción de Friedel-Crafts es una piedra angular para la introducción de sustituyentes de carbono en las arenas.
Su aplicación en variantes asimétricas está limitada a sustratos activados debido a las restricciones de nucleofilicidad del areno.

Objetivo del estudio:

Desarrollar una reacción asimétrica de Friedel-Crafts aplicable a las arenas no activadas.
Para permitir la síntesis de ésteres de arilglicina enriquecidos con enantio a partir de arenas simples de hidrocarburos.

Principales métodos:

Se han utilizado organocatalizadores de ácido de Brønsted fuertes y confinados.
Utilizó N,O-acetales como socios electrófilos.
Reacciones investigadas con arenos no activados, alkoxibenzos y heteroarenos.

Principales resultados:

Se ha logrado una formación de enlaces C-C altamente regionales y estereoselectivos.
Realizó con éxito la primera reacción catalítica asimétrica de Friedel-Crafts en alquilbenzenos simples.
Generó ésteres de arilglicina enriquecidos con enantio de sustratos previamente inaccesibles.

Conclusiones:

Superó la limitación de la nucleofilicidad del sustrato en las reacciones asimétricas de Friedel-Crafts.
Amplió la utilidad de la alquilación de Friedel-Crafts a través de la organocatálisis asimétrica.
Abrió el camino para aplicaciones más amplias de síntesis asimétrica en química orgánica.

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