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Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
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Los ligandos olefinos con deficiencia de electrones permiten la generación de carbonos cuaternarios por acoplamiento
Chung-Yang Dennis Huang1, Abigail G Doyle1
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|April 17, 2015
Resumen
Los investigadores desarrollaron un nuevo método de acoplamiento cruzado Negishi catalizado por Ni. Este enfoque produce eficientemente valiosas fenetilaminas β-sustituidas, creando carbonos cuaternarios a través de una nueva vía de eliminación reductora.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis por catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Las reacciones de acoplamiento cruzado Negishi son vitales para la formación de enlaces C-C.
- La síntesis de fenetilaminas β-sustituidas, especialmente aquellas con carbono cuaternario, sigue siendo un reto.
- El desarrollo de sistemas catalíticos eficientes para transformaciones desafiantes es un área clave en la síntesis orgánica.
Objetivo del estudio:
- Para desarrollar una nueva reacción de acoplamiento cruzado de Negishi catalizada por Ni.
- Para sintetizar fenetilaminas β-sustituidas con centros de carbono cuaternarios.
- Identificar y utilizar un nuevo ligando que mejore la eficiencia y la selectividad de la reacción.
Principales métodos:
- Reacción de acoplamiento cruzado Negishi catalizada por níquel.
- Utilizando aziridinas de estirenilo 1,1-disubstituidas como socios de acoplamiento.
- Empleando un nuevo ligando de olefinas con deficiencia de electrones, Fro-DO.
Principales resultados:
- La síntesis exitosa de las valiosas fenetilaminas β-sustituidas.
- Se logró una eliminación reductiva desafiante para formar un centro de carbono cuaternario.
- El ligando Fro-DO permitió altas tasas de reacción y quimioselectividad, suprimiendo la eliminación de β-H.
- El ligando es de fácil acceso, estable y modular.
Conclusiones:
- Se ha establecido un nuevo y eficiente método de acoplamiento cruzado de Negishi catalizado por Ni para sintetizar fenetilaminas β-sustituidas.
- El nuevo ligando Fro-DO es crítico para el éxito de la reacción, ofreciendo un alto rendimiento y selectividad.
- La naturaleza modular de Fro-DO sugiere potencial para el desarrollo de nuevas transformaciones catalíticas.
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