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Síntesis práctica y regioselectiva de las piridinas C-4-alquiladas

Jin Choi¹, Gabriele Laudadio¹, Edouard Godineau²

¹Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States.

Journal of the American Chemical Society

|July 28, 2021

Resumen

Un nuevo grupo de bloqueo derivado del maleato permite la alquilación directa C-4 de las piridinas. Este avance simplifica el acceso a valiosos bloques de construcción de piridina utilizando la química del tipo Minisci en la piridina nativa.

Área de la Ciencia:

Química orgánica
Química Heterocíclica

Sus antecedentes:

La alquilación directa de C-4 por posición selectiva de las piridinas es un desafío.
Los métodos anteriores se basaban en piridinas prefuncionalizadas para prevenir las reacciones secundarias.

Objetivo del estudio:

Desarrollar un método para la alquilación directa C-4 de las piridinas nativas.
Para permitir el acceso barato a los valiosos bloques de construcción de piridina.

Principales métodos:

Se inventó un grupo de bloqueo derivado del maleato para las piridinas.
Este grupo permite una alquilación descarboxilada controlada del tipo Minisci en la posición C-4.

Principales resultados:

El método proporciona un control exquisito sobre la alquilación de C-4.
Es aplicable a varias piridinas y donantes de alquilo.
El proceso es operacionalmente simple, escalable y rentable.

Conclusiones:

Esta estrategia permite la funcionalización temprana de las piridinas nativas.
Ofrece una desviación significativa de los enfoques tradicionales de funcionalización en etapas avanzadas.
El método desarrollado proporciona un acceso rápido y económico a importantes estructuras de piridina.

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