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Conexión multicomponente catalizada por níquel de dimetilzinco, alquinas, 1,3-butadieno, aldehídos y aminas
Masanari Kimura1, Keisuke Kojima, Yasushi Tatsuyama
1Department of Applied Chemistry, Faculty of Engineering, and Graduate School of Science and Technology, Nagasaki University, 1-14 Bunkyo, Nagasaki 852-8521, Japan.
Journal of the American Chemical Society
|May 11, 2006
Resumen
Un catalizador de níquel (0) permite una reacción de cinco componentes que incluye dimetilzinco, alquinas, butadieno, aldehídos y aminas. La reacción selectivamente produce compuestos 1 o 2 basados en el tipo de amina (aromática o alifática).
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Los catalizadores de níquel son versátiles en las transformaciones orgánicas.
- Las reacciones de cinco componentes ofrecen rutas sintéticas eficientes.
- El control de la selectividad en las reacciones multicomponentes es un desafío clave.
Objetivo del estudio:
- Desarrollar una nueva reacción de cinco componentes catalizada por níquel (0).
- Para lograr la síntesis selectiva de los productos 1 y 2.
- Para investigar la influencia de la estructura de aminas en el resultado de la reacción.
Principales métodos:
- Utilizando una especie de níquel (((0) como catalizador.
- Reaccionan el dimetilzinco, las alquinas, el 1,3-butadieno, los aldehídos y las aminas.
- Varios sustratos de aminas (aromáticos frente a alifáticos) para estudiar la selectividad.
Principales resultados:
- Se logró una reacción de acoplamiento exitosa de cinco componentes.
- Formación selectiva del producto 1 con aminas aromáticas.
- Formación selectiva del producto 2 con aminas alifáticas.
- Se informaron buenos rendimientos para ambos productos.
Conclusiones:
- Un catalizador de níquel ((0) media efectivamente un nuevo acoplamiento de cinco componentes.
- La elección de la amina dicta la formación selectiva de cualquiera de los productos 1 o 2.
- Esta metodología proporciona una ruta versátil a moléculas complejas.
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