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Diclorinación radical electrocatalítica de alquenos con fuentes de cloro nucleófilas
Niankai Fu1, Gregory S Sauer1, Song Lin1,2
1Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States.
Journal of the American Chemical Society
|October 10, 2017
Resumen
Un nuevo método electroquímico catalizado por el manganeso permite la diclorinación de alquenos utilizando cloruro de magnesio. Este proceso sostenible crea eficientemente dicloruros vecinos, incluso con grupos funcionales sensibles, a través de la transferencia de átomos de cloro mediada por metales.
Área de la Ciencia:
- Química orgánica
- La electroquímica
- Catálisis
Sus antecedentes:
- La síntesis electroquímica ofrece una alternativa sostenible a los métodos químicos tradicionales.
- El desarrollo de sistemas catalíticos eficientes para la funcionalización de alceno es crucial en la síntesis orgánica.
Objetivo del estudio:
- Desarrollar un nuevo método electroquímico catalizado por el manganeso para la diclorinación de alquenos.
- Utilizar el cloruro de magnesio como una fuente de cloro accesible y rentable.
- Para lograr una alta quimioselectividad para la síntesis de dicloruro vicinal, especialmente con sustratos oxidativamente sensibles.
Principales métodos:
- Dicloración electroquímica de varios alquenos utilizando un catalizador de manganeso.
- Utilizando el cloruro de magnesio como fuente de cloro.
- Investigar el mecanismo de reacción a través de estudios mecanicistas.
Principales resultados:
- Síntesis exitosa de diversos compuestos dichlorados en las proximidades.
- Se ha observado una alta quimioselectividad para los alquenos que contienen grupos funcionales oxidativamente lables (alcoholes, aldehídos, sulfuros, aminas).
- Los datos mecánicos apoyan una vía de transferencia de átomos de Cl mediada por metales, excluyendo la participación directa del gas cloro.
Conclusiones:
- El método desarrollado ofrece una vía sencilla, sostenible y eficiente para los dicloruros vecinos.
- El enfoque electroquímico catalizado por el manganeso es altamente quimioselectivo, conservando grupos funcionales sensibles.
- Los hallazgos aclaran el mecanismo de reacción, destacando la transferencia de cloro mediada por metales como el paso clave.
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