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Síntesis total de (-) -cilindrociclfano A facilitado por la funcionalización C-H

Aaron T Bosse¹, Liam R Hunt², Camila A Suarez^1,2

¹Department of Chemistry, Emory University, Atlanta, GA 30322, USA.

Science (New York, N.Y.)

|November 7, 2024

Resumen

Los investigadores desarrollaron una síntesis eficiente de 17 pasos para el (-) -cilindrociclfano A, un macrociclo complejo. Esta ruta simplificada utiliza funcionalización C-H avanzada y reacciones de acoplamiento cruzado para una alta estereoselectividad.

Área de la Ciencia:

Química orgánica
Química sintética
Catálisis

Sus antecedentes:

El (-) -cilindrociclano A es un producto natural macrocíclico complejo con un núcleo de [7.7]paraciclano.
Su estructura presenta funcionalidad de bis-resorcinol y seis estereocentros, lo que plantea desafíos sintéticos significativos.

Objetivo del estudio:

Desarrollar una estrategia sintética simplificada y altamente enantioselectiva para el (-) -cilindrociclfano A.
Para demostrar el poder de los métodos catalíticos modernos en la síntesis de moléculas complejas.

Principales métodos:

Se utilizaron 10 reacciones de funcionalización de C-H, incluida la catálisis quiral de tetracarboxilato de dirodio para enlaces primarios y secundarios de C-H.
Se utilizan acoplamientos cruzados C(sp2)-C(sp2) catalizados por el paladio para construir el núcleo macrocíclico.
Incorpora una acetoxilación cuadruplicada C ((sp2)-H catalizada por el paladio en etapa tardía para instalar fracciones de bis-resorcinol.

Principales resultados:

Se logró una síntesis total de 17 pasos de (-) -cilindrociclfano A con una alta eficiencia general.
Se ha demostrado una alta regioselectividad, diastereoselectividad y enantioselectividad durante toda la síntesis.
Instalado con éxito los seis estereocentros y la funcionalidad de bis-resorcinol.

Conclusiones:

La estrategia sintética desarrollada ofrece una mejora significativa con respecto a los enfoques anteriores.
Este trabajo pone de relieve la eficacia de combinar la funcionalización C-H y las reacciones de acoplamiento cruzado en la síntesis total compleja.
Hace hincapié en el valor de la colaboración entre laboratorios en el avance de la química sintética.

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