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Rhodium ((III) - Indolización atroposelectiva catalizada para el acceso a los macrociclos planar-chiral

Hongxuan Zhai¹, Kang Lv², Jiayan Li¹

¹Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.

Journal of the American Chemical Society

|October 9, 2024

Resumen

Este estudio introduce un nuevo método catalizado por el rodio para la síntesis de macrociclos complejos con indolos planar-quirales. El nuevo enfoque permite la construcción eficiente de complejas estructuras macrocíclicas de carbono en un solo paso.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los macrociclos que contienen indoles prevalecen en los productos naturales con actividad biológica.
La síntesis de indoles planar-quirales enantioméricamente puros a través de la macrociclación sigue siendo un desafío sintético significativo.

Objetivo del estudio:

Desarrollar la primera síntesis catalítica enantioselectiva de indoles planar-quirales a través de la macrociclización.
Establecer un protocolo catalizado por el rodio para la macrociclización atroposelectiva que incluya la activación y anulación de C-H.

Principales métodos:

La activación C-H catalizada por el rodio de la anilina.
Anulación oxidativa [3 + 2] con una alquina intramolecular.
Macrociclado atroposelectivo para formar índolos planar-quirales.

Principales resultados:

Un nuevo protocolo de un solo paso para la construcción de indol, macrociclismo y control de la quiralidad plana.
Síntesis exitosa de atropisómeros macrocíclicos con cadenas ansa de carbono completo desafiantes.
Los estudios termodinámicos indicaron una barrera de rotación más baja para las cadenas ansa de carbono completo en comparación con las cadenas oxa-ansa.

Conclusiones:

El método desarrollado catalizado por rodio proporciona una ruta eficiente a los atropisómeros macrocíclicos complejos.
Los estudios computacionales aclararon el mecanismo, destacando la activación de C-H y la inserción de alquina como clave para la enantioselectividad.
Este trabajo supera un obstáculo importante en la síntesis de indoles planar-quirales macrocíclicos.

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