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Updated: May 16, 2025

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes

Published on: September 12, 2018

Iodación de transferencia catalizada por paladio de yoduros de arilo a enlaces C3-H no activados

Emilien Le Saux¹, Bill Morandi¹

¹Laboratorium für Organische Chemie, ETH Zürich, 8093 Zürich, Switzerland.

Journal of the American Chemical Society

|April 4, 2025

Resumen

Los investigadores desarrollaron un nuevo método catalítico para la iodación de enlaces C ((sp3) -H utilizando yoduros de arilo. Esta catálisis de paladio habilitada por la luz ofrece un enfoque suave y versátil para funcionalizar enlaces químicos desafiantes.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La funcionalización de los enlaces C ((sp3) -H no activados sigue siendo un desafío importante en la síntesis orgánica.
El desarrollo de métodos eficientes y suaves para la iodación de enlaces C-H es crucial para crear moléculas complejas.
La catálisis de paladio ofrece potentes herramientas para la funcionalización de C-H, pero su alcance se está expandiendo a sustratos no activados.

Objetivo del estudio:

Informar sobre una nueva estrategia para la iodación catalítica de los enlaces C ((sp3) -H no activados.
Desarrollar un método que utilice yoduros de arilo como reactivos de transferencia de átomos de hidrógeno y donantes de yodo.
Aplicar este mecanismo para la tiolación de C ((sp3) -H.

Principales métodos:

Fusión de la lanzadera y la catálisis de paladio habilitada para la luz.
Utilizando un ciclo catalítico no canónico Pd0/PdI.
Utilizando ioduros de arilo como reactivos de doble función.

Principales resultados:

La iodación catalítica exitosa de enlaces C ((sp3) -H no activados bajo condiciones suaves.
Demostración de la tolerancia del grupo funcional, incluidos los grupos sensibles.
Aplicación del mecanismo a la tiolación de C ((sp3) -H a través de pasos reversibles.

Conclusiones:

La estrategia presentada proporciona un método eficiente y versátil para la iodación de C ((sp3) -H.
El sistema catalítico de paladio desarrollado funciona en condiciones suaves y tolera varios grupos funcionales.
Los conocimientos mecanicistas permiten aplicaciones adicionales, como la tiolación de C ((sp3) -H.

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