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Migración/carbonización/ciclización de carbenos catalizados: construcción directa de precursores de ario

Guohao Zhu¹, Wen-Chao Gao¹, Xuefeng Jiang^1,2

¹Shanghai Key Laboratory of Green Chemistry and Chemical Process, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, P. R. China.

Journal of the American Chemical Society

|January 13, 2021

Resumen

Una nueva reacción catalizada por Rh (I) crea fenólicos orto-sililo-sustituidos a partir de diinas de sililo. Este método proporciona acceso directo a precursores arinos completamente sustituidos para la construcción de moléculas aromáticas policíclicas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

El acceso a fenólicos y arinas sustituidos es crucial en la síntesis orgánica.
Los métodos existentes a menudo requieren múltiples pasos o carecen de control sobre la selectividad.

Objetivo del estudio:

Desarrollar una nueva reacción en cascada catalizada por Rh para la síntesis de fenólicos sustituidos por ortocilos.
Permitir un acceso eficiente a los precursores de aryne completamente sustituidos.
Aplicar esta metodología para la construcción de moléculas aromáticas policíclicas.

Principales métodos:

Reacción en cascada catalizada por el rodio que implica la formación de carbenoides.
Ciclificación carbonilativa de las diinas de silicio.
Fluorosulfurilación en un solo paso para la generación de precursores de aryne.

Principales resultados:

Se sintetizaron diversos fenólicos sustituidos por orto sililo.
El grupo sililo suprimió efectivamente la oxidación y controló la selectividad de inserción de monóxido de carbono.
Se estableció una ruta directa a las arinas completamente sustituidas.
Se demostró su aplicación en la síntesis de moléculas aromáticas policíclicas.

Conclusiones:

La reacción en cascada catalizada por Rh (I) desarrollada es un método eficiente para sintetizar valiosos intermedios fenólicos y arinos.
Esta metodología ofrece un enfoque simplificado para estructuras aromáticas policíclicas complejas.

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