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

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

Published on: January 17, 2020

Catálisis asimétrica a través de iones de oxocarbenio cíclicos y alifáticos

Sunggi Lee¹, Philip S J Kaib¹, Benjamin List¹

¹Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.

Journal of the American Chemical Society

|February 8, 2017

Resumen

Un nuevo catalizador de imidodifosforimidato (IDPi) permite la síntesis enantioselectiva directa de diversos heterociclos de oxígeno a partir de acetato de lactol y enolisilanos, logrando una excelente enantioselectividad.

Área de la Ciencia:

Química orgánica
Catálisis
Química sintética

Sus antecedentes:

Los heterociclos de oxígeno son frecuentes en los productos farmacéuticos y naturales.
La síntesis enantioselectiva eficiente de estos andamios sigue siendo un desafío clave en la química orgánica.

Objetivo del estudio:

Desarrollar una vía sintética enantioselectiva directa para los heterociclos de oxígeno sustituidos.
Utilización de un nuevo catalizador de imidodifosforimidato (IDPi) para esta transformación.

Principales métodos:

Reacción de los acetatos de lactol con los enol silanos.
Utilizando un catalizador de imidodifosforimidato (IDPi) altamente reactivo y confinado.
Análisis de la enantioselectividad de los productos de reacción.

Principales resultados:

Síntesis enantioselectiva directa exitosa de varios heterociclos de oxígeno, incluidos los tetrahidrofuranos, los tetrahidropiranos, los oxepanos, los cromanos y los dihidrobenzofuranos.
Se obtuvieron excelentes enantioselectividades para los heterociclos quirales sintetizados.
Los estudios mecanicistas indicaron una vía que involucra un intermediario de iones de oxocarbenio cíclico.

Conclusiones:

El método desarrollado catalizado por IDPi proporciona un acceso eficiente a los heterociclos de oxígeno enriquecidos enantioméricamente.
Esta metodología ofrece una herramienta valiosa para la síntesis de moléculas quirales complejas.
El contraanión quiral confinado juega un papel crucial en el control de la enantioselectividad.

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