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Quimioselectividad en el reordenamiento diotrópico basado en Pd: desarrollo y aplicación en la síntesis total de

Jing Gong¹, Qian Wang¹, Jieping Zhu¹

¹Laboratory of Synthesis and Natural Products (LSPN), Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, CH-1015 Lausanne, Switzerland.

Journal of the American Chemical Society

|January 15, 2025

Resumen

Este estudio demuestra la modulación de grupos de desplazamiento en el reordenamiento diotrópico catalizado por paladio utilizando Selectfluor. El método sintetiza eficientemente tetrahidropiranolos fluorados y 6,8-dioxabiciclo[3.2.1]octanos (DOBCO), incluidas las feromonas clave.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

El reordenamiento diotrópico a menudo produce mezclas de productos debido a múltiples conformadores.
El control de la selectividad en estas reorganizaciones sigue siendo un reto.

Objetivo del estudio:

Desarrollar un método para modular grupos cambiantes en el reordenamiento diotrópico catalizado por paladio.
Para sintetizar los tetrahidropiranolos fluorados y los 6,8-dioxabiciclo[3.2.1]octanos (DOBCO).

Principales métodos:

Utilizando sales de paladio (II) y Selectfluor con γ-hidroxialquenos o γ,δ-dihidroxialquenos.
El uso de un proceso de dominó que implica la activación y la funcionalización secuenciales de enlaces C-C y C-Pd.
Investigando las vías mecanicistas que incluyen oxipaladación, oxidación de Pd y reordenamiento diotrópico.

Principales resultados:

Se obtiene una formación controlada de tetrahidropiranolos fluorados y DOBCO.
Se ha demostrado una conformación controlada, quimio-selectiva C ((sp3) -C ((sp3) y C ((sp3) -Pd ((IV) enlaces metátesis.
Se estableció una nueva desconexión retrosintética para la síntesis de DOBCO.

Conclusiones:

El reordenamiento diotrópico catalizado por Pd ofrece un control preciso sobre los grupos cambiantes.
Esta metodología proporciona un acceso eficiente a éteres cíclicos complejos y estructuras DOBCO.
La síntesis desarrollada es valiosa para preparar moléculas biológicamente relevantes, como las feromonas como la (+) -frontalina.

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