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Updated: Aug 20, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

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La catálisis por relés de ligandos permite la acilación reductora migratoria asimétrica de olefinas o haluros de

Xiaoli Jiang¹, Feng-Tao Sheng¹, Yao Zhang¹

¹State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210093, China.

Journal of the American Chemical Society

|November 17, 2022

Resumen

Este estudio introduce un enfoque sinérgico de doble ligando para las reacciones catalizadas por níquel-hidruro. Este método produce eficientemente cetonas quirales alfa-arilo a partir de materiales de partida simples con una alta selectividad.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

El diseño de ligandos es crucial para las reacciones asimétricas catalizadas por metales de transición.
Los efectos sinérgicos de múltiples ligandos pueden mejorar la eficiencia catalítica y la selectividad a través del intercambio dinámico de ligandos.

Objetivo del estudio:

Aplicar el concepto de ligandos múltiples sinérgicos en reacciones catalizadas por níquel-hidruro.
Desarrollar un método eficiente para la síntesis de cetonas quirales alfa-arilo.

Principales métodos:

Se utilizó una hidroacilación remota catalizada por NiH de olefinas y una acilación migratoria de haluros de alquilo.
Se emplearon dos ligandos simples: uno para el paseo en cadena y otro para la acilación asimétrica.

Principales resultados:

Se ha logrado una excelente regioselectividad y enantioselectividad en las reacciones objetivo.
Se ha sintetizado con éxito una amplia gama de cetonas quirales alfa-arilo enriquecidas con enantio.
Se ha demostrado una síntesis eficiente en condiciones suaves a partir de alceno/alquilo haluros y ácidos carboxílicos abundantes.

Conclusiones:

La estrategia sinérgica de doble ligando es efectiva para la hidroacilación remota asimétrica catalizada por NiH y la acilación migratoria.
Este enfoque proporciona una ruta versátil a las valiosas cetonas quirales alfa-arilo.

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