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Mecanismo de activación del óxido nitroso en las reacciones de formación de enlaces C2O catalizadas por complejos de

Lorenzo Baldinelli¹, Paola Belanzoni¹, Giovanni Bistoni¹

¹Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy.

Journal of the American Chemical Society

|February 20, 2024

Resumen

Los complejos de níquel activan el óxido nitroso (N2O) para la transferencia de oxígeno en la formación de enlaces C-O. La actividad redox de los ligandos permite la catálisis, con factores electrónicos y geométricos que guían las vías de reacción para el diseño de nuevos catalizadores.

Área de la Ciencia:

Química organometálica
Catálisis
Química computacional

Sus antecedentes:

Los complejos de níquel con ligandos basados en bipiridina activan el óxido nitroso (N2O) como agente de transferencia de oxígeno.
Esta activación permite la formación de enlaces C(sp2) O en condiciones suaves.

Objetivo del estudio:

Elucidar el mecanismo catalítico de la activación de N2O por complejos de Ni utilizando cálculos químicos cuánticos.
Proporcionar conocimientos fundamentales para el desarrollo de nuevos catalizadores para la revalorización del N2O.

Principales métodos:

Se emplearon cálculos químicos cuánticos.
Un estudio de caso basado en Cornella et al. (Nature, 2022) para la síntesis de fenol a partir de haluros de arilo fue analizado.

Principales resultados:

El centro de Ni permanece en el estado de oxidación de Ni (II) durante todo el ciclo catalítico.
La actividad redox del ligando, que acepta electrones de un agente reductor, es crucial para la catálisis.
Las vías catalíticas están influenciadas por las propiedades electrónicas del ligando (fuerza de campo) y la geometría (brazos de coordinación).

Conclusiones:

El diseño de ligandos es fundamental para controlar las vías catalíticas frente a las estequiométricas.
Las características del ligando modulador permiten el desarrollo de catalizadores de Ni con propiedades redox y reactividad adaptadas para la utilización de N2O.

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