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Funcionalización regioselectiva controlada por carbenos de alcanos lineales bajo catálisis de plata

María Álvarez¹, Francisco Molina¹, Pedro J Pérez¹

¹Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Química Sostenible and Departamento de Química, Universidad de Huelva, 21007 Huelva, Spain.

Journal of the American Chemical Society

|December 13, 2022

Resumen

Los investigadores desarrollaron un nuevo método catalizado por plata para funcionalizar los enlaces C-H en los alcanos. Este enfoque utiliza complejos de plata específicos y reactivos diazo para controlar la regioselectividad, lo que permite la modificación selectiva de los sitios primarios o secundarios.

Área de la Ciencia:

Química orgánica
Catálisis
Funcionalidad C-H

Sus antecedentes:

El control de la regioselectividad en la funcionalización de alcano C-H a través de la transferencia de carbeno es típicamente dependiente del catalizador, a menudo utilizando catalizadores de rodio con reactivos diazoespecíficos.
Los métodos existentes se basan principalmente en el catalizador para dictar el resultado de la reacción.

Objetivo del estudio:

Presentar una estrategia alternativa para la funcionalización regioselectiva de C-H de los alcanos lineales.
Demostrar un control regional independiente del catalizador y regido por el reactivo diazoeléctrico.

Principales métodos:

Utilizó complejos de plata con ligandos de trispirazolíborato como catalizadores.
Se utilizaron varios reactivos diazo, incluidos los diazoacetatos de arilo donante y el diazoacetato de etilo aceptador.
Investigó la funcionalidad de los alcanos lineales como el hexano y el pentano.

Principales resultados:

La regioselección lograda se rige principalmente por el reactivo diazo, no por el catalizador.
Los diazoacetatos de arilo donante-aceptor han funcionalizado selectivamente los enlaces secundarios C-H.
El acetato de etilo receptor logró una funcionalización sin precedentes de los enlaces primarios C-H.

Conclusiones:

Desarrolló un nuevo sistema catalizado por plata para la funcionalización C-H con compuestos diazo.
Demostró que el reactivo diazo, en lugar del catalizador, puede dictar la regioselectividad en la funcionalización de alcano.
Se han abierto nuevas vías para la modificación selectiva de alcano mediante el control de la funcionalización en sitios primarios o secundarios.

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