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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Una investigación computacional y experimental del origen de la selectividad en la reacción de Minisci
Kristaps Ermanis1, Avene C Colgan1, Rupert S J Proctor1
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom.
Journal of the American Chemical Society
|November 30, 2020
Resumen
La reacción de Minisci
Área de la Ciencia:
- Química orgánica
- Catálisis
- Química medicinal
Sus antecedentes:
- La reacción de Minisci es un método clave para la funcionalización de los heteroarenos.
- La catálisis con ácido fosfórico quiral permite reacciones enantioselectivas de Minisci.
- Anteriormente, el mecanismo de reacción y el origen de la selectividad no estaban claros.
Objetivo del estudio:
- Para aclarar el mecanismo de las reacciones enantioselectivas de Minisci.
- Para identificar el paso que determina la estereoquímica.
- Comprender el origen de la alta enantioselectividad y regioselectividad.
Principales métodos:
- Estudios mecanicistas experimentales.
- Cálculos de la Teoría Funcional de la Densidad (DFT).
- Análisis de los radicales intermedios catiónicos y las vías de desprotonación.
Principales resultados:
- La evidencia apoya el control de Curtin-Hammett, con enantioselectividad determinada durante la desprotonación.
- Los cálculos de DFT revelaron una inesperada desprotonación interna por el grupo amida.
- Esta desprotonación no convencional, ayudada por el fosfato quiral, dicta la selectividad.
Conclusiones:
- Se estableció un modelo mecanicista detallado para las reacciones enantioselectivas de Minisci.
- El papel del grupo amida en la desprotonación interna es crucial para la selectividad.
- Los hallazgos facilitan una aplicación más amplia de este valioso método sintético.
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