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Superar los problemas de selectividad en la catálisis reversible: una hidrocianatión de transferencia que exhibe un

Benjamin N Bhawal^1,2, Julia C Reisenbauer^1,2, Christian Ehinger¹

¹ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland.

Journal of the American Chemical Society

|June 2, 2020

Resumen

Este estudio introduce un nuevo método de transferencia de hidrocianato reversible para la síntesis selectiva de nitriles ramificados. Este avance ofrece un enfoque práctico y libre de HCN para la síntesis química compleja.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Las reacciones catalíticas reversibles son difíciles de controlar selectivamente debido a las limitaciones termodinámicas.
El logro de la selectividad cinética en reacciones reversibles es crucial para las aplicaciones sintéticas.

Objetivo del estudio:

Desarrollar un sistema catalítico selectivo para la transferencia reversible de hidrocianato.
Para lograr una alta selectividad para el isómero ramificado termodinámicamente menos favorable.

Principales métodos:

Explotación de barreras cinéticas más bajas para la formación/escisión de enlaces C-CN en posiciones bencílicas.
Diseño de un nuevo donante de cianuro de hidrógeno (HCN) para un protocolo práctico sin HCN.
Utilizando una reacción de transferencia reversible sin un ácido de Lewis cocatalítico.

Principales resultados:

Alta selectividad para el isómero de nitrilo ramificado en una reacción de transferencia reversible de hidrocianado.
Demostración de un protocolo práctico de transferencia de hidrocianato sin HCN.
Resolución sintética exitosa de isómeros de nitrilo ramificados y lineales.

Conclusiones:

Se puede lograr una alta selectividad cinética en reacciones de transferencia reversibles.
El protocolo desarrollado abre nuevas aplicaciones sintéticas para reacciones reversibles.
Este trabajo avanza en el campo de la catálisis selectiva en la síntesis orgánica.

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