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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)

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Published on: January 17, 2020

Las reacciones de eneno catalizadas por escandio enantioselectivas sinselectivas catalizadas por escandio

David A Evans¹, Jimmy Wu

¹Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA. evans@chemistry.harvard.edu

Journal of the American Chemical Society

|June 2, 2005

Resumen

Los complejos quiral escandio piridil bis ((oxazolina) catalizan las reacciones de carbonilo-eno con alto exceso y rendimiento enantiomérico. Este método produce eficientemente productos sintéticos a partir de olefinas trisubstituidas, lo que demuestra un excelente control estéreo.

Área de la Ciencia:

Química orgánica es la química orgánica.
Catalización asimétrica por catálisis asimétrica.
Química organometálica Química orgánica de los metales.

Sus antecedentes:

La reacción de carbonilo-eno es una transformación valiosa que forma enlaces carbono-carbono en la síntesis orgánica.
El desarrollo de variantes enantioselectivas y diastereoselectivas es crucial para la síntesis de moléculas quirales.
Los ácidos quirales de Lewis, particularmente los basados en escandio, han demostrado ser prometedores en la catalización de reacciones asimétricas.

Objetivo del estudio:

Desarrollar un nuevo sistema catalítico para las reacciones enantioselectivas y diastereoselectivas de carbonilo-eno.
Para investigar la eficacia de los complejos quirales de escandio piridil bis (oxazolina) (pybox) como catalizadores.
Para lograr altos rendimientos y estereoselectividades en la formación de productos de carbonileno.

Principales métodos:

Síntesis y caracterización de los complejos quirales de escandio piridil bis ((oxazolina) (pybox).
Aplicación de estos complejos como catalizadores en la reacción del carbonileno con varios sustratos.
Análisis de los productos de reacción utilizando técnicas para determinar el rendimiento, el exceso enantiomérico (ee) y la relación diastereomérica (dr).

Principales resultados:

Los complejos quirales de pybox de escandio catalizaron efectivamente la reacción del carbonilo-ene.
Se observaron excesos enantioméricos uniformemente altos y buenos rendimientos en diferentes sustratos.
La reacción utilizando olefinas trisubstituidas produjo selectivamente el producto de síntesis con alta enantio- y diastereoselectividad.

Conclusiones:

Se ha establecido un sistema catalítico altamente eficaz para las reacciones asimétricas de carbonileno utilizando complejos quirales de pybox de escandio.
La metodología desarrollada proporciona una ruta confiable a los productos quirales con un excelente control estereoquímico.
Este enfoque es particularmente eficiente para la síntesis de productos de síntesis a partir de olefinas trisubstituidas.

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