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Aminación de arilo con sales de Ni (II) libres de ligandos y catálisis por fotorreducción

Emily B Corcoran¹, Michael T Pirnot², Shishi Lin³

¹Merck Center for Catalysis at Princeton University, Princeton, NJ 08544, USA.

Science (New York, N.Y.)

|June 25, 2016

Resumen

Los investigadores desarrollaron un nuevo método de catálisis fotorredóxica para la aminación de arilo. Este enfoque utiliza sales simples de níquel para formar enlaces carbono-nitrógeno, ofreciendo una alternativa a los sistemas complejos de ligandos en la síntesis química.

Área de la Ciencia:

Química orgánica
Catálisis
La fotoquímica

Sus antecedentes:

La aminación catalizada por metales de transición de haluros de arilo es crucial para la síntesis de anilinas, prevalentes en productos farmacéuticos y productos químicos finos.
Los métodos existentes a menudo se basan en ligandos especializados para facilitar la eliminación reductiva de los centros metálicos.
Existe la necesidad de métodos complementarios y generales que eviten el diseño complejo de ligandos.

Objetivo del estudio:

Desarrollar un nuevo método general para la formación de enlaces carbono-nitrógeno.
Explorar la catálisis fotorredóxica para desestabilizar complejos de amido metálico como una alternativa a las estrategias basadas en ligandos.
Establecer un paradigma mecanicista distinto para la aminación de arilo.

Principales métodos:

Utilizó la catálisis fotorredóxica para inducir la transferencia de electrones.
Se utilizan sales de níquel sin ligandos como sistema catalítico.
Investigó la desestabilización de los centros metálicos de níquel para facilitar la eliminación reductiva.

Principales resultados:

Demostró un paradigma mecanicista distinto para la aminación de arilo.
Se ha conseguido una fácil eliminación reductora de los centros metálicos del níquel.
Se han formado con éxito enlaces carbono-nitrógeno mediante un evento de transferencia de electrones catalizado por fotorreducción.

Conclusiones:

La catálisis fotorredóxica ofrece una estrategia viable para la aminación de arilo mediante la desestabilización de complejos de amido metálico.
Las sales de níquel sin ligandos proporcionan un sistema catalítico eficiente para esta transformación.
Este enfoque presenta una alternativa complementaria a los métodos tradicionales intensivos en ligandos en la síntesis orgánica.

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