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La N-acilación catalítica y enantioselectiva de lactamas y tiolactamas mediante el uso de catalizadores basados en

Xing Yang¹, Valentina D Bumbu, Peng Liu

¹Department of Chemistry, Washington University, One Brookings Drive, St. Louis, Missouri 63130, USA.

Journal of the American Chemical Society

|October 4, 2012

Resumen

Los lactamos y tiolactamos racemicos ahora se pueden resolver utilizando la N-acilación asimétrica con catalizadores de amidina. Este método ofrece una alta enantioselectividad, superando las limitaciones de las técnicas de resolución tradicionales para estos compuestos.

Área de la Ciencia:

Química orgánica es la química orgánica.
Catalización asimétrica por catálisis asimétrica.

Sus antecedentes:

Los lactamos y tiolactamos racemicos son difíciles de resolver utilizando métodos convencionales como la acilación enzimática o la resolución clásica.
Los alcoholes y las aminas, a diferencia de los lactamas y los tiolactamas, pueden resolverse más fácilmente mediante técnicas establecidas.

Objetivo del estudio:

Desarrollar un método conveniente y eficaz para la resolución cinética de lactamos y tiolactamos racémicos.
Para lograr una alta enantioselectividad en el proceso de resolución de estos valiosos compuestos.

Principales métodos:

Se emplearon reacciones asimétricas de N-acilación, utilizando catalizadores basados en amidina como Cl-PIQ 2 y BTM 3.
Se realizaron cálculos de la teoría funcional de la densidad (DFT) para dilucidar el mecanismo de reacción y los aspectos de reconocimiento quiral.

Principales resultados:

Los catalizadores basados en amidina, específicamente Cl-PIQ 2 y BTM 3, demostraron eficacia en la resolución cinética de lactamas y tiolactamas.
Con frecuencia se lograron excelentes niveles de enantioselectividad en el proceso asimétrico de N-acilación.
Los cálculos de DFT confirmaron que la reacción se produce a través de la N-acilación del tautómero lactim.
Se identificaron interacciones catión-π como cruciales para el reconocimiento quiral de sustratos de lactamo durante el proceso catalítico.

Conclusiones:

La N-acilación asimétrica catalizada por derivados de amidina proporciona una estrategia viable y eficiente para la resolución de lactamas y tiolactamas racémicos.
La comprensión del mecanismo de reacción, que involucra la acilación del tautómero lactim y las interacciones catión-π, ayuda en el diseño de catalizadores más efectivos para el reconocimiento quiral.

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