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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI

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Funcionalización selectiva de las piridinas a través de sales heterocíclicas de fosfonio

Michael C Hilton¹, Ryan D Dolewski¹, Andrew McNally¹

¹Department of Chemistry, Colorado State University , Fort Collins, Colorado 80523, United States.

Journal of the American Chemical Society

|October 13, 2016

Resumen

Ahora es posible funcionalizar directamente las piridinas en la posición 4. Este nuevo método de dos pasos crea éteres heteroariles valiosos a partir de estructuras complejas de piridina y otros heterociclos.

Área de la Ciencia:

Química orgánica
Química medicinal
Ciencias de los materiales

Sus antecedentes:

Los derivados de piridina son bloques de construcción cruciales en productos farmacéuticos, agroquímicos y materiales avanzados.
La funcionalización directa C-H ofrece rutas sintéticas eficientes, pero la modificación selectiva de la piridina sigue siendo un desafío.

Objetivo del estudio:

Desarrollar un nuevo método para la funcionalización selectiva de C-H en la posición 4 de las piridinas.
Demostrar la utilidad de este método para la síntesis de éteres heteroariles y otros compuestos valiosos.

Principales métodos:

Una secuencia de reacción de dos pasos que implica la transformación de los enlaces C-H de 4 posiciones de piridina en grupos C-PPh3+.
Conversión posterior del intermediario C-PPh3+ en éteres heteroarilicos.

Principales resultados:

El método desarrollado funcionaliza selectivamente la posición 4 de las piridinas.
La secuencia es efectiva para derivados complejos de piridina, compuestos farmacéuticos y varios heterociclos.
Las investigaciones iniciales indican susceptibilidad a las formaciones de enlace C-C, C-N y C-S.

Conclusiones:

Este trabajo proporciona una nueva y poderosa herramienta para la funcionalización de la piridina.
El método ofrece una plataforma versátil para acceder a diversas moléculas que contienen piridina para diversas aplicaciones.

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