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Funcionalización estereoselectiva de reactivos ciclopropilzinco racemicos a través del acoplamiento de relés

Lun An¹, Fei-Fei Tong¹, Shu Zhang²

¹Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

Journal of the American Chemical Society

|June 13, 2020

Resumen

Este estudio introduce una estrategia enantiodivergente para la síntesis de ciclopropanos quirales a partir de reactivos ciclopropilzinco racémicos. El método produce eficientemente valiosos ciclopropanos quirales con configuraciones opuestas para aplicaciones químicas medicinales.

Área de la Ciencia:

Química orgánica
Síntesis asimétrica

Sus antecedentes:

La catálisis de metales de transición es clave para crear moléculas quirales.
La síntesis de ciclopropanos quirales a partir de precursores racémicos es un desafío debido a las dificultades en la formación intermedia estereoselectiva.

Objetivo del estudio:

Desarrollar una estrategia enantidivergente eficiente para sintetizar diversos ciclopropanos quirales.
Utilización de reactivos ciclopropilzinco racémicos para la creación de ciclopropanos enriquecidos enantioméricamente.

Principales métodos:

Un proceso de acoplamiento de relés enantidivergente de una sola olla y dos pasos.
Resolución cinética catalizada por níquel de los reactivos racémicos cis-ciclopropilzinco.
Acoplamiento de relés estéreo específico con varios electrófilos.

Principales resultados:

Síntesis eficiente de ciclopropanos quirales funcionalizados, incluidas las variantes de cadena lateral fluoroalquiladas y quirales.
Producción de dos tipos de ciclopropanos quirales con configuraciones opuestas a partir de un solo material de partida racémico.
Demostración de la versatilidad de los ciclopropanos quirales como sintetizadores.

Conclusiones:

La estrategia de acoplamiento de relés enantiodivergente proporciona acceso a diversos ciclopropanos quirales.
Este método supera las limitaciones en el uso de nucleófilos alquilmetálicos secundarios racémicos.
Los ciclopropanos quirales sintetizados son valiosos para crear moléculas estructuralmente diversas con aplicaciones medicinales potenciales.

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