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Hidroacilación catalizada por CuH enantioselectiva empleando ácidos carboxílicos insaturados como sustitutos del

Yujing Zhou¹, Jeffrey S Bandar¹, Stephen L Buchwald¹

¹Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.

Journal of the American Chemical Society

|June 2, 2017

Resumen

Este estudio introduce una nueva reacción catalizada por hidruro de cobre para la creación de cetonas quirales α-arilo dialquilo a partir de ácidos insaturados y alquenos arilo. El método demuestra un amplio alcance de sustrato, tolerando diversos grupos funcionales y heterociclos para una mayor utilidad sintética.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

La hidroacilación asimétrica directa de alquenos sigue siendo un desafío importante en la síntesis orgánica.
Los métodos existentes a menudo carecen del alcance del sustrato y la tolerancia del grupo funcional requeridos para la síntesis de moléculas complejas.

Objetivo del estudio:

Desarrollar una nueva reacción de acoplamiento asimétrico directo con hidruro de cobre (CuH).
Sintetizar cetonas quirales α-arilo dialquilo con una amplia aplicabilidad y tolerancia de grupo funcional.

Principales métodos:

Utilizó el acoplamiento directo asimétrico de hidróxido de cobre (CuH) de ácidos carboxílicos α,β insaturados con alquenos arilo.
Investigó la tolerancia de la reacción a varios patrones de sustitución de sustratos, grupos funcionales sensibles y heterociclos.

Principales resultados:

Se han sintetizado con éxito cetonas quirales α-arilo dialquilo.
Se ha demostrado un amplio alcance del sustrato, alojando diversos grupos funcionales y fracciones heterocíclicas.
Se ha logrado una expansión significativa de los productos accesibles en comparación con los métodos de hidroacilación existentes.

Conclusiones:

El acoplamiento catalizado por CuH reportado proporciona una nueva y poderosa ruta a las cetonas quirales α-arilo dialquilo.
La metodología ofrece una mayor utilidad sintética debido a su amplia tolerancia de grupo funcional.
Propuso un mecanismo que involucra la silición catalizada por CuH de ácidos insaturados, generando un intermediario electrófilo clave.

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