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Funcionalización electrofotocatalítica C-H de éteres con alta regioselectividad

He Huang¹, Zack M Strater², Tristan H Lambert^1,2

¹Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States.

Journal of the American Chemical Society

|January 7, 2020

Resumen

Este estudio introduce un nuevo método electrofotocatalítico para la funcionalización C-H de éteres utilizando iones de trisaminociclopropenio (TAC). El proceso logra una alta regioselectividad, acoplando éteres con varios compuestos en condiciones suaves.

Área de la Ciencia:

Química orgánica
Fotocatálisis
La electro-síntesis

Sus antecedentes:

La funcionalización C-H es una transformación clave en la síntesis orgánica.
La electrofotocatálisis ofrece rutas sintéticas sostenibles.
Los iones de trisaminociclopropenio (TAC) son fotocatalizadores emergentes.

Objetivo del estudio:

Desarrollar una funcionalización C-H electrofotocatalítica de éteres altamente selectiva por región.
Explorar el acoplamiento de éteres con varios compuestos insaturados y heterocíclicos.
Para aclarar el mecanismo de reacción que involucra a los iones TAC.

Principales métodos:

La electrofotocatálisis mediante el uso de iones trisaminociclopropenio (TAC).
Irradiación de luz visible bajo un potencial electroquímico leve.
Reacciones de acoplamiento sin oxidantes.

Principales resultados:

Funcionalización C-H altamente regioselectiva de éteres en la posición α menos obstaculizada.
Acoplamiento exitoso con isoquinolinas, alquenos, alquinas, pirazoles y purinas.
Demostración de un nuevo mecanismo de transferencia de átomos de hidrógeno (HAT).

Conclusiones:

Los iones de trisaminociclopropenio (TAC) permiten una eficiente y regioselectiva funcionalización del éter C-H.
El método desarrollado proporciona una nueva vía para sintetizar moléculas orgánicas complejas.
El estudio pone de relieve un nuevo modo de reactividad para los electrofotocatalizadores.

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