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Síntesis total enantioselectiva de los disiherboles A, C y D

Shengkun Hu¹, Yefeng Tang²

¹Department of Chemistry, Tsinghua University, Beijing 100084, China.

Journal of the American Chemical Society

|October 13, 2022

Resumen

Este estudio detalla la síntesis total enantioselectiva de los disiherboles A, C y D, sesquiterpenos únicos. Los pasos sintéticos clave incluyen una cicloadición inducida por foto y un reordenamiento aniónico, que conduce a estructuras revisadas para los disiherboles C y D.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Química computacional

Sus antecedentes:

Los disiherboles A, C y D son sesquiterpenos pentacíclicos complejos con estructuras únicas de quinona e hidroquinona.
Las asignaciones estructurales anteriores para los disiherboles C y D pueden requerir revisión.

Objetivo del estudio:

Para lograr la primera síntesis total enantioselectiva de los disiherboles A, C y D.
Para aclarar el mecanismo de una clave [1,2]-aniónica reordenamiento.
Revisar las estructuras de los disiherboles C y D basándose en pruebas sintéticas.

Principales métodos:

Síntesis total enantioselectiva utilizando una cicloadición [2 + 2] quinona-alqueno inducida por la luz.
El uso de un tándem de reordenamiento [1,2]-aniónico / fragmentación de ciclopropano como un paso sintético clave.
Realización de estudios computacionales detallados para investigar el mecanismo de reacción.

Principales resultados:

Síntesis total enantioselectiva exitosa de los disiherboles A, C y D.
Estructuras revisadas para los disiherboles C y D basadas en el resultado sintético.
El análisis computacional reveló un mecanismo concertado para el reordenamiento [1,2]-aniónico, impulsado por la liberación de la tensión del anillo y la aromaticidad del estado de transición.

Conclusiones:

La estrategia sintética desarrollada proporciona acceso a los disiherboles y a los compuestos relacionados.
El estudio ofrece información mecanicista sobre un reordenamiento aniónico sin precedentes.
Los hallazgos contribuyen a la comprensión de los complejos mecanismos de síntesis y reacción de los productos naturales.

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