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Resolución cinética catalizada por ácido fosfórico quiral a través de la formación de enlaces amídicos

Yasushi Shimoda¹, Hisashi Yamamoto¹

¹Molecular Catalyst Research Center, Chubu University , 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan.

Journal of the American Chemical Society

|May 11, 2017

Resumen

La catálisis con ácido quiral de Brønsted permite la resolución cinética de los ésteres 2-piridil a través de la formación de enlaces amídicos. Un ácido fosfórico quiral específico logró altas selectividades, con los ácidos de Lewis mejorando aún más la reactividad y la selectividad de los sustratos sustituidos por methoxy.

Área de la Ciencia:

Química orgánica
Catálisis asimétrica

Sus antecedentes:

La resolución cinética es crucial para obtener compuestos enantioméricamente puros.
Los ésteres de 2-piridil son productos intermedios sintéticos versátiles.

Objetivo del estudio:

Desarrollar un sistema catalítico para la resolución cinética de los ésteres 2-piridil.
Investigar la eficacia de los ácidos quirales de Brønsted en la formación de enlaces amídicos.

Principales métodos:

Resolución cinética de un éster de 2-piridil.
Formación de enlaces amídicos catalizados por un ácido Brønsted quiral.
Utilización de un ácido fosfórico quiral específico (grupo 2,4,6-trimetilo-3,5-dinitrofenilo en la posición 3,3').
Investigación de los aditivos de ácido de Lewis.

Principales resultados:

Se lograron elevadas selectividades en la resolución cinética.
El ácido fosfórico quiral catalizó efectivamente la formación de enlaces amídicos.
La adición de ácido de Lewis mejoró tanto la reactividad como la selectividad de los sustratos con un grupo metoxico.

Conclusiones:

La catálisis con ácido quiral de Brønsted es un método viable para la resolución cinética de los ésteres 2-piridil.
El sistema catalítico desarrollado ofrece una alta eficiencia y selectividad.
Los aditivos de ácido de Lewis pueden optimizar aún más la transformación para sustratos específicos.

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