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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

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Pd(II) - Anulación asimétrica [4 + 1] mediante inserción carbenilativa habilitada por relés de ligandos / cascada de

Zhou Luo^1,2, Yi-Hao Zhang², Chao Zhang¹

¹School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai 200062, China.

Journal of the American Chemical Society

|January 22, 2026

Resumen

Este estudio introduce una nueva anulación asimétrica catalizada por el paladio para crear compuestos cíclicos quirales. El nuevo método sintetiza eficientemente indanonas enriquecidas con enantio con α-alquilideno 3-sustituido utilizando una reacción de inserción de carbenos en tándem/Heck.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

La anulación asimétrica catalizada por el paladio es crucial para sintetizar compuestos cíclicos quirales.
El desarrollo de estrategias eficientes para estas transformaciones sigue siendo un desafío importante en la síntesis orgánica.

Objetivo del estudio:

Para reportar una estrategia de anulación asimétrica sin precedentes catalizada por el paladio.
Proporcionar un protocolo eficiente para acceder a las indanonas α-alquilidenas 3-sustituidas enantio-enriquecidas.

Principales métodos:

Utilizando una vía de reacción de inserción y migración de carbenos en tándem.
El uso de una estrategia de relé de ligando asimétrico para controlar la enantioselectividad.
Realización de estudios mecanicistas, incluidos experimentos de control y cálculos de DFT.

Principales resultados:

Se ha logrado una síntesis eficiente de indanonas α-alquilidenas 3-sustituidas enriquecidas con enantio.
Se ha demostrado un amplio alcance de sustrato con una enantioselectividad de buena a excelente.
Elucidado un nuevo mecanismo E1cB para la etapa de eliminación de Heck a través de cálculos DFT.

Conclusiones:

El método desarrollado ofrece una vía eficiente para obtener valiosos derivados quirales de la indanona.
Las ideas mecánicas revelan el sistema de relevo de ligando y un nuevo mecanismo E1cB.
La etapa de enantiodeterminación implica una formación concertada de carbenos y un proceso de inserción migratoria.

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