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La aminopiridilación selectiva de alquenos con ylidos de aminopiridinio habilitados para la luz visible

Yonghoon Moon^1,2, Wooseok Lee^1,2, Sungwoo Hong^1,2

¹Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.

Journal of the American Chemical Society

|July 3, 2020

Resumen

Los investigadores desarrollaron una aminopiridilación orto-selectiva de alquenos inducida por luz visible utilizando ylidos de N-aminopiridinio. Este método instala de manera eficiente grupos amino y piridil en diversos alquenos a través de la cicloadición dipolar 1,3-mediada por radicales en condiciones suaves y libres de metales.

Área de la Ciencia:

Química orgánica
Fotocatálisis
Metodología sintética

Sus antecedentes:

Los ylidos de N-aminopiridinio poseen una reactividad poco explorada.
Las cicloadiciones 1,3-dipolares mediadas por radicales ofrecen vías para la síntesis de moléculas complejas.

Objetivo del estudio:

Desarrollar una aminopiridilación orto-selectiva de alquenos inducida por la luz visible.
Utilización de los ylidos de N-aminopiridinio en una nueva cicloadición mediada por radicales.

Principales métodos:

Fotocatálisis con luz visible para la oxidación de un solo electrón de ylidos de N-aminopiridinio.
Cicloadición 1,3-dipolar mediada por radicales con varios sustratos de alqueno.
Condiciones de reacción sin metales.

Principales resultados:

Exitosa aminopiridilación orto-selectiva de alquenos activados y no activados.
Formación de beta-aminoetilpiridinas a través de la escisión homolítica del enlace N-N.
Control modular de la orto-selectividad y la sindiastereoselectividad.

Conclusiones:

El método desarrollado proporciona un acceso eficiente a valiosos andamios de beta-aminoetilpiridina.
La reacción se produce en condiciones suaves y libres de metales, lo que mejora su utilidad sintética.
Los estudios experimentales y computacionales aclararon el mecanismo y los orígenes de la selectividad.

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