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Acoplamiento reductor regioselectivo y estereoselectivo de alquinos y crotonitrilo

Kun Cui^1,2, Yan-Lin Li¹, Gongqiang Li²

¹State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.

Journal of the American Chemical Society

|December 8, 2022

Resumen

Un nuevo método de catálisis dual con luz visible permite el acoplamiento reductivo regio y estereoselectivo de alquinos y crotononitril. Este proceso sintetiza eficientemente nitriles homoalílicos enriquecidos con enantio utilizando condiciones suaves y fuentes de hidrógeno sostenibles.

Área de la Ciencia:

Química orgánica
Catálisis
La fotoquímica

Sus antecedentes:

El desarrollo de métodos eficientes para sintetizar moléculas quirales es crucial en la química orgánica.
Las reacciones de acoplamiento reductivo son importantes para la formación de enlaces carbono-carbono.
La fotocatálisis con luz visible ofrece un enfoque sostenible para impulsar las transformaciones químicas.

Objetivo del estudio:

Desarrollar una nueva reacción de acoplamiento reductivo regio y estereoselectivo.
Para sintetizar nitriles homoalílicos enriquecidos con enantio con un alto control de la geometría de los alquenos.
Para explorar el uso de la luz visible organophotoredox cobalto doble catálisis.

Principales métodos:

Se utiliza la doble catálisis de cobalto organofotoredóxido con luz visible para el acoplamiento de alquinos y crotononitril.
Se utilizaron condiciones de reacción suaves.
Investigó el uso de una base orgánica y agua como fuentes de hidrógeno.

Principales resultados:

Se obtiene una elevada regioselectividad (hasta >20:1 rr) y estereoselectividad (>20:1 E/Z) en la síntesis de nitriles homoalílicos.
Se obtienen productos con una enantioselectividad excelente (hasta el 98% ee).
Demostró la conversión de productos de nitrilo en varios bloques de construcción quirales.

Conclusiones:

Se ha establecido un método novedoso y eficiente para la síntesis de nitriles homoalílicos enriquecidos con enantio.
El sistema de catálisis dual desarrollado proporciona un excelente control de la regioselectividad, estereo selectividad y enantioselectividad.
El uso de fuentes sostenibles de hidrógeno (base orgánica y agua) pone de relieve los aspectos de química verde de esta transformación.

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