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La β-protonación enantioselectiva mediante una estrategia de catálisis cooperativa

Michael H Wang¹, Daniel T Cohen¹, C Benjamin Schwamb¹

¹Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Northwestern University, Silverman Hall, Evanston, Illinois 60208, United States.

Journal of the American Chemical Society

|May 2, 2015

Resumen

Un nuevo sistema de catalizador cooperativo con carbenos N-heterocíclicos (NHCs) permite una β-protonación enantioselectiva altamente selectiva. Este enfoque de organocatálisis produce eficientemente derivados de succinato enriquecidos con enantio de los arilo-oxobutenoatos.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Síntesis asimétrica de síntesis.

Sus antecedentes:

Los carbenos N-heterocíclicos (NHC, por sus siglas en inglés) son organocatalizadores versátiles.
La β-protonación asimétrica es crucial para la síntesis de moléculas quirales.
La catálisis cooperativa puede mejorar la eficiencia de reacción y la selectividad.

Objetivo del estudio:

Desarrollar un método de β-protonación enantioselectivo catalizado por carbenos N-heterocíclicos (NHC).
Investigar el efecto cooperativo de tres organocatalizadores distintos.
Para sintetizar eficientemente derivados de succinato altamente enriquecidos con enantio.

Principales métodos:

Desarrollo de un sistema de tres organocatalisadores. desarrollo de un sistema de tres organocatalisadores.
Utilizando la catálisis NHC para la β-protonación.
Reacción de los aril-oxobutenoatos con el sistema catalizador.

Principales resultados:

Se obtienen altos rendimientos y enantioselectividades en la β-protonación.
Se ha demostrado la conversión eficiente de los aril-oxobutenoatos en derivados de succinato.
Mostró un rendimiento mejorado en comparación con la catálisis solo con NHC.

Conclusiones:

El sistema de catalizador cooperativo mejora significativamente el rendimiento y la selectividad.
Este método ofrece una ruta eficiente a los derivados de succinato enriquecidos con enantio.
La combinación de diferentes modos de activación en la organocatálisis es beneficiosa.

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