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Reacción de carboiodinación promovida por la luz azul - Evidencia para la formación de enlaces C-I reversibles a

Austin D Marchese¹, Andrew G Durant¹, Cian M Reid¹

¹Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, OntarioCanada, M5S 3H6.

Journal of the American Chemical Society

|October 28, 2022

Resumen

Una nueva reacción catalizada por el paladio utiliza la luz azul para crear moléculas orgánicas yodadas. Este método eficiente trabaja con grupos funcionales sensibles y produce valiosos compuestos heterocíclicos.

Área de la Ciencia:

Química orgánica
Catálisis
La fotoquímica

Sus antecedentes:

La catálisis del paladio es crucial para la formación de enlaces C-C y C-heteroatomo.
El desarrollo de reacciones de carboiodinación eficientes y selectivas sigue siendo un área activa de investigación.
La catálisis fotorredóxica con luz visible ofrece un enfoque sostenible para la síntesis orgánica.

Objetivo del estudio:

Para reportar una nueva reacción de carboiodinación catalizada por paladio (0) / luz azul.
Desarrollar un sistema catalítico sencillo y estable para la síntesis de heterociclos yodados.
Investigar el mecanismo de reacción, incluida la función de la transferencia de electrones individuales.

Principales métodos:

Utilizando un precursor de paladio ([Pd(allyl) Cl]2) y un ligando de fosfina (DPEPhos).
Empleando radiación de luz azul para impulsar el ciclo catalítico.
Reaccionando con varios sustratos para generar una biblioteca de compuestos yodados.

Principales resultados:

Sintetizó con éxito una serie de heterociclos yodados, incluidos los oxindoles, los dihidrobenzofuranos y las indolinas.
Tolerancia demostrada a los grupos funcionales sensibles como los ácidos carboxílicos, los fenoles, las anilinas y las piridinas.
Se obtienen altos rendimientos del producto, hasta el 94%.

Conclusiones:

El sistema de luz azul desarrollado proporciona una ruta eficiente para la carboiodinación.
El protocolo es robusto y tolera diversos grupos funcionales, expandiendo su utilidad sintética.
Los estudios mecánicos sugieren una formación de enlace C-I reversible a través de una única vía de transferencia de electrones.

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