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Deshidrogenación o lactonización catalizada por el cobre de los enlaces C
Shupeng Zhou1, Zi-Jun Zhang1, Jin-Quan Yu2
1Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA.
Nature
|March 28, 2024
Resumen
Los investigadores desarrollaron un método catalizado por cobre para la funcionalización remota C-H de ácidos alifáticos utilizando N-metoxiamidas. Este nuevo enfoque permite una deshidrogenación o lactonización eficientes, ofreciendo una herramienta versátil para la síntesis química.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- Las enzimas del citocromo P450 catalizan la oxidación bimodal de los ácidos alifáticos.
- El desarrollo de sistemas catalíticos análogos para la funcionalización remota de C-H es un desafío.
Objetivo del estudio:
- Desarrollar un sistema catalizado por Cu (I) para la funcionalización remota de C-H de las N-metoxamidas.
- Para lograr reacciones de deshidrogenación/lactonización bimodal a través de abstracciones radicales.
Principales métodos:
- Utilizó N-metoxiamidas como precursores de radicales y oxidantes internos.
- Se utiliza un catalizador de cobre para la funcionalización C-H.
- Se estudió el control de las condiciones de reacción para el cambio entre deshidrogenación y lactonización.
Principales resultados:
- Se ha logrado la deshidrogenación/lactonización bimodal catalizada por Cu (I) de las N-metoxiamidas.
- Se ha demostrado la funcionalización redox-neutral de C-H con metanol como único subproducto.
- Se ha aplicado con éxito el sistema catalítico a diversos ácidos alifáticos, incluidas las moléculas de fármacos y los productos naturales, con una carga de catalizador baja (0,5 mol%).
Conclusiones:
- Desarrolló un sistema catalítico versátil y eficiente para la funcionalidad remota de C-H.
- Se destacó la ventaja de utilizar sustratos simples de amida como oxidantes internos suaves.
- Mostró la compatibilidad del sistema con varias funcionalidades sensibles a la oxidación.
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