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Hidrogenación de transferencia catalizada por cobalto controlada por ligando de alquinas: síntesis estereodivergente

Shaomin Fu¹, Nan-Yu Chen^1,2, Xufang Liu¹

¹Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University , Beijing 100084, China.

Journal of the American Chemical Society

|June 21, 2016

Resumen

Este estudio introduce un nuevo catalizador de cobalto para la hidrogenación estereoselectiva de alquinos, produciendo alquenos Z o E. El método eficiente funciona con diversos grupos funcionales y bajas cantidades de catalizador.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La hidrogenación alquínica es una transformación fundamental en la síntesis orgánica.
El control de la estereoselectividad en la reducción de alquinas sigue siendo un desafío.
El desarrollo de sistemas catalíticos eficientes y selectivos es crucial para acceder a isómeros de alquenos específicos.

Objetivo del estudio:

Desarrollar un nuevo método catalizado por cobalto para la hidrogenación de transferencia estereodivergente de alquinas.
Lograr un control efectivo de la selectividad de los alquenos Z y E mediante el diseño racional del catalizador.
Demostrar la amplia aplicabilidad y las condiciones suaves del sistema catalítico desarrollado.

Principales métodos:

El uso de un nuevo catalizador de cobalto para las reacciones de hidrogenación por transferencia.
Utilización de fuentes de hidrógeno disponibles para el proceso de reducción.
Investigando el diseño del catalizador para el control de la estereoselectividad.

Principales resultados:

Síntesis estereodivergente exitosa de los alquenos Z y E a partir de las alquinas.
Se obtienen altos rendimientos y una excelente quimioselectividad y estereoselectividad para más de 50 sustratos.
Aplicabilidad demostrada a las alquinas con diversos grupos funcionales.
Se requiere una carga de catalizador baja (0,2 mol %) para una transformación eficiente.

Conclusiones:

Se ha establecido una nueva hidrogenación de transferencia estereodivergente catalizada por cobalto de alquinas.
El método ofrece una ruta suave y eficiente a los alquenos Z y E con una amplia tolerancia de grupo funcional.
Los hallazgos proporcionan una herramienta valiosa para sintetizar alquenos específicamente sustituidos.

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