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Isomerización de las olefinas estereoselectivas catalizadas por cobalto: fácil acceso a los alquenos tricíclicos

Sheng Zhang¹, Deepika Bedi¹, Lu Cheng¹

¹Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States.

Journal of the American Chemical Society

|April 22, 2020

Resumen

Un nuevo catalizador de cobalto permite una síntesis eficiente y estereoselectiva de alquenos trisubstituidos a partir de alquenos 1,1-disubstituidos. Este método ofrece una alternativa escalable para crear moléculas orgánicas complejas.

Área de la Ciencia:

Química orgánica
Catálisis

Sus antecedentes:

La síntesis estereoselectiva de alquenos trisubstituidos es un desafío debido a las pequeñas diferencias de energía entre los isómeros E/Z.
La isomerización catalizada por metales de transición de alquenos 1,1-disubstituidos está subdesarrollada para una síntesis eficiente y estereoselectiva de alquenos trisubstituidos.

Objetivo del estudio:

Desarrollar un método eficiente y estereoselectivo para la síntesis de alquenos trissubstituidos.
Para superar las limitaciones en los protocolos de isomerización existentes para la síntesis de alceno trisubstituido.

Principales métodos:

Desarrollo de un nuevo catalizador de cobalto para la isomerización de alquenos.
Investigación del mecanismo de reacción, incluida una vía de hidruro de cobalto.
Aplicación del protocolo para sintetizar luminóforos orgánicos y alquenos deuterados.

Principales resultados:

El nuevo catalizador de cobalto proporciona un acceso eficiente y estereoselectivo a una amplia gama de alquenos trisubstituidos.
El protocolo demuestra compatibilidad con mono- y dienes, buena tolerancia del grupo funcional y escalabilidad.
El mecanismo de reacción implica una vía de hidruro de cobalto, con una alta estereoselectividad atribuida al apilamiento π-π y al obstáculo estérico.

Conclusiones:

Un nuevo método de isomerización catalizado por cobalto ofrece una solución eficaz para la síntesis estereoselectiva de alqueno trisubstituido.
Este protocolo expande las capacidades sintéticas para los luminóforos orgánicos y los compuestos etiquetados isotópicamente.
Los hallazgos proporcionan información sobre el ciclo catalítico y los factores estereodeterminantes.

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