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Acceso a las β-lactamas a través de la oxidación de olefinas catalizadas por hierro habilitada por el ligando de

Jeonguk Kweon^1,2, Dongwook Kim^1,2, Seungju Kang³

¹Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea.

Journal of the American Chemical Society

|January 18, 2022

Resumen

Este estudio introduce un método catalizado por hierro utilizando dioxazolonas para crear andamios β-lactámicos. El ligando de ftaalocianina es clave para la generación de radicales intermedios, lo que permite una síntesis eficiente de estructuras lactámicas valiosas.

Área de la Ciencia:

Química orgánica
Catálisis
Química medicinal

Sus antecedentes:

Los andamios β-lactámicos son motivos estructurales cruciales en muchos productos farmacéuticos.
La síntesis eficiente y selectiva de estos andamios sigue siendo un desafío importante en la química orgánica.

Objetivo del estudio:

Desarrollar una nueva reacción de oxyamidación catalizada por hierro para sintetizar andamios β-lactámicos.
Investigar el mecanismo de la reacción e identificar los factores clave para su eficiencia y selectividad.

Principales métodos:

Utilización de dioxazolonas atadas como precursores de nitrenoides en reacciones catalizadas por el hierro.
El uso de ligandos de ftaalocianina para modular la actividad catalítica del hierro.
Realización de estudios mecanicistas para aclarar la vía de reacción, incluida la formación de radicales intermedios.

Principales resultados:

Desarrollo exitoso de una oxyamidación de olefinas catalizada por hierro para la síntesis de β-lactam.
Identificación del papel crítico de la capacidad de aceptación de π del ligando de ftaalocianina en la formación de un intermediario triplo de radicales de hierro-imidilo.
Demostración de una alta diastereoselectividad en el proceso de exolactamización por 4-trig.
Ampliación de la metodología para lograr una síntesis de γ-lactamo altamente eficiente con un alto volumen de negocios (TON > 300).

Conclusiones:

La oxyamidación catalizada por hierro desarrollada proporciona una ruta novedosa y eficiente a los valiosos andamios β-lactámicos y γ-lactámicos.
Los conocimientos mecanicistas destacan la importancia del diseño del ligando en el control de los intermedios radicales para la ciclización selectiva.
Este enfoque ofrece una estrategia prometedora para la síntesis de heterociclos complejos que contienen nitrógeno.

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