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Un modo distinto de reactividad cíclica Allene impulsada por deformación: migración de grupo al átomo de carbono

Qian Xu¹, Thomas R Hoye¹

¹Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States.

Journal of the American Chemical Society

|April 22, 2023

Resumen

Los alenos cíclicos se pueden transformar en fenoles sustituidos utilizando una nueva estrategia de migración de grupo. Este método supera las limitaciones de las reacciones tradicionales, permitiendo la síntesis de moléculas complejas.

Área de la Ciencia:

Química orgánica
Química sintética

Sus antecedentes:

Los alenos cíclicos tensados son productos intermedios altamente reactivos.
Los 1,2,4-ciclohexatrienos son una subclase de alenos cíclicos generados a través de las reacciones tetradehidro-Diels-Alder.
Una limitación clave es su tendencia a isomerizar a los benzenoides.

Objetivo del estudio:

Desarrollar una nueva vía sintética para los fenoles sustituidos.
Para superar la limitación de isomerización de los alenos cíclicos.
Explorar la nueva reactividad de los éteres silílicos de enol y los ésteres de enol en la química alénica cíclica.

Principales métodos:

Generación de 1,2,4-ciclohexatrienos a partir de 1,3-enienos que contienen alquinos atados.
Modificación del componente enyne con éteres silílicos de enol o ésteres de enol
Estudios experimentales y cálculos de la teoría funcional de la densidad (DFT).

Principales resultados:

La modificación del éter silílico o el éster enólico dirige la migración de grupo (silílico o acílico) en lugar de la migración de hidrógeno.
Esta nueva reactividad conduce a la formación de productos fenólicos altamente sustituidos, como los fenoles o-silílicos.
La migración de grupo ocurre desde el átomo de oxígeno hasta el carbono central del alleno.

Conclusiones:

Se ha establecido un nuevo método para sintetizar fenoles sustituidos a partir de alenos cíclicos.
Esta estrategia controla efectivamente la reactividad de los alenos cíclicos, evitando la isomerización no deseada.
Los hallazgos ofrecen una herramienta valiosa para introducir la complejidad molecular en la síntesis orgánica.

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