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La α-hidroarilación catalítica de acrilatos y acrilamidas a través de una reacción de hidrodehalogenación

Alena M Vasquez¹, John A Gurak¹, Candice L Joe²

¹Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States.

Journal of the American Chemical Society

|May 8, 2020

Resumen

Un nuevo método catalizado por el paladio permite la hidroarilación selectiva de acrilatos y acrilamidas. Esta reacción es tolerante a diversos grupos funcionales y procede a través de un intermediario clave de hidruro de paladio para una alta selectividad.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La hidroarilación es una reacción crucial para la formación de enlaces carbono-carbono.
El desarrollo de métodos selectivos y tolerantes a los grupos funcionales sigue siendo un desafío.

Objetivo del estudio:

Informar de una nueva hidroariación α selectiva catalizada por el paladio de acrilatos y acrilamidas.
Investigar el alcance y las limitaciones de esta nueva transformación.
Para aclarar el mecanismo de reacción y entender el origen de la selectividad.

Principales métodos:

Catalización con paladio
Reacción de hidroarilación
Estudios mecánicos
Evaluación del ámbito de aplicación del sustrato

Principales resultados:

Se obtiene una hidroarilación α-selectiva de acrilatos y acrilamidas utilizando un catalizador de paladio.
Se ha demostrado una alta tolerancia al grupo funcional, incluidos los grupos sensibles a las bases y los carbonilos múltiples enolizables.
Se ha identificado un intermediario [PdII(Ar) ((H) ] responsable de la inserción selectiva del hidruro.

Conclusiones:

El método desarrollado ofrece una poderosa nueva vía para sintetizar compuestos de carbonilo sustituidos por arilo funcionalizados.
Las ideas mecanicistas proporcionan una base para un mayor desarrollo de catalizadores y reacciones.
Este trabajo amplía el conjunto de herramientas para la formación selectiva de enlaces C-C en la síntesis orgánica.

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