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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
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Ciclización catalítica enantioselectiva/acoplamiento cruzado con electrófilos de alquilo
1Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|March 1, 2014
Resumen
Este estudio introduce un nuevo método de síntesis asimétrica catalítica utilizando catalizadores de níquel/diamina para crear moléculas complejas. El enfoque permite la formación de nuevos enlaces carbono-carbono y estereocentros en dihidrobenzofuranos e indanos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- La expansión del alcance de las reacciones de acoplamiento cruzado con electrófilos alquilo es crucial para la síntesis orgánica.
- Las olefinas colgantes en los socios de acoplamiento nucleófilo ofrecen oportunidades para la formación de enlaces secuenciales.
- La síntesis asimétrica catalítica es vital para producir compuestos enantioméricamente puros.
Objetivo del estudio:
- Desarrollar una nueva estrategia catalítica asimétrica para la síntesis de 2,3-dihidrobenzofuranos y indanos.
- Para explorar la utilidad de un acoplamiento cruzado catalizado de níquel/diamina con olefinas colgantes.
- Para demostrar la aplicación de este método en la construcción de arquitecturas moleculares complejas.
Principales métodos:
- Utilizando un sistema de catalizador de níquel/diamina para las reacciones de acoplamiento cruzado.
- Empleando sustratos con olefinas colgantes para facilitar la inserción de las β-migrantes.
- Realización de síntesis asimétrica catalítica con control sobre múltiples estereocentros.
Principales resultados:
- Estableció la viabilidad del enfoque para la síntesis de 2,3-dihidrobenzofuranos e indanes.
- Aplicó con éxito el método para sintetizar el núcleo de dihidrobenzofurano de fasiglifam.
- Control demostrado sobre dos estereocentros, incluido uno recién generado a través de la inserción β-migratoria, utilizando un catalizador quiral con un electrofilo racémico.
Conclusiones:
- El método desarrollado proporciona una ruta eficiente para la síntesis asimétrica catalítica de valiosos compuestos cíclicos.
- Esta estrategia permite la formación de nuevos enlaces C-C y estereocentros, mejorando la complejidad molecular.
- El enfoque es aplicable tanto a la síntesis de núcleos de productos naturales como al acoplamiento estereoselectivo de sustratos racémicos.
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