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Aleación asimétrica C3 de las piridinas

Zhong Liu¹, Zhu-Jun Shi¹, Lu Liu¹

¹State Key Laboratory and Institute of Elemento-Organic Chemistry, Haihe Laboratory of Sustainable Chemical Transformations, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China.

Journal of the American Chemical Society

|May 18, 2023

Resumen

Este estudio introduce la alilación asimétrica C-H de las piridinas en la posición C3, una nueva transformación. El nuevo método utiliza la catálisis en tándem de borano e iridio para una síntesis eficiente de valiosos derivados de piridina.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La funcionalización C-H es un área clave en la síntesis orgánica.
La funcionalización asimétrica C-H de las piridinas, especialmente en la posición C3, sigue siendo un desafío significativo.
El desarrollo de nuevos sistemas catalíticos para la modificación selectiva de piridina es crucial para el descubrimiento de fármacos.

Objetivo del estudio:

Informar sobre los primeros ejemplos de funcionalización asimétrica intermolecular C-H de las piridinas en la posición C3.
Desarrollar un nuevo protocolo para la alilación C3 de las piridinas utilizando catálisis en tándem.
Para permitir la funcionalización en etapa tardía de los compuestos que contienen piridina.

Principales métodos:

Un enfoque catalítico en tándem que incluye catalizadores de borano e iridio.
Hidroboración catalizada por boro de las piridinas para formar dihidropiridinas nucleófilas.
Alilación enantioselectiva catalizada por iridio de las dihidropiridinas.
Aromatización oxidativa mediante el uso del aire como oxidante.

Principales resultados:

Se ha logrado una alilación asimétrica C3 de piridinas.
Se obtiene una elevada enantioselectividad (hasta > 99% ee).
Se ha demostrado su idoneidad para la funcionalización de las moléculas de fármacos en etapas avanzadas.

Conclusiones:

Se ha establecido un método nuevo y sin precedentes para la alelación asimétrica C3 de las piridinas.
El protocolo desarrollado ofrece acceso directo a las piridinas aliadas C3 enantioméricamente enriquecidas.
Esta metodología tiene un potencial significativo para la síntesis de productos farmacéuticos complejos que contienen piridina.

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