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Updated: Jul 1, 2025

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

Marco orgánico covalente homoquiral tridimensional con topología quiral intrínseca

Xing Kang¹, Cheng Cheng¹, Xu Chen¹

¹School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China.

Journal of the American Chemical Society

|March 14, 2024

Resumen

Los investigadores desarrollaron nuevos marcos orgánicos covalentes 3D (COF) que integran la quiralidad molecular, la helicidad y la topología quiral intrínseca. Estos materiales porosos quirales son prometedores para una mayor enantioselectividad en la catálisis.

Área de la Ciencia:

Ciencias de los materiales
Química orgánica
Catálisis

Sus antecedentes:

Los materiales estructurales porosos quirales son valiosos, pero rara vez combinan la quiralidad molecular, la helicidad y la topología quiral intrínseca 3D.
Tales características combinadas son cruciales para la transferencia eficiente de quiralidad y la amplificación en los materiales.

Objetivo del estudio:

Para sintetizar nuevos marcos orgánicos covalentes 3D (COF) con una topología quiral intrínseca.
Investigar la integración de las características homoquirales y homohélicas dentro de estos COF.
Explorar la aplicación catalítica de estos COFs quirales en reacciones asimétricas.

Principales métodos:

Síntesis de dos COF 3D isostruturales mediante la condensación imina de las tetraaminas de porfirina y los dienos enantiopuros.
Caracterización de la estructura de las COF, incluida la topología qzd no interpenetrada y la disposición helicoidal de la porfirina.
Metalización posintética con Rh (I) para crear un catalizador heterogéneo (CCOF 23).

Principales resultados:

Síntesis exitosa de los dos primeros COF 3D con una topología quiral intrínseca y propiedades homoquirales/homohelicas integradas.
La geometría y la flexibilidad del enlace de dieno en forma de V dictan la alineación de la porfirina, creando estructuras helicoidales.
El COF metalizado (CCOF 23) demostró una alta enantioselectividad en adición asimétrica de Michael, superando a los catalizadores homogéneos debido a los canales helicoidales confinados.

Conclusiones:

Este trabajo presenta una nueva clase de COFs 3D multiquirales con características topológicas y helicoidales únicas.
Los hallazgos ofrecen información sobre la generación y el control de la helicidad en estado sólido, la homociralidad y la enantioselectividad.
Estos materiales son prometedores para aplicaciones avanzadas en catálisis asimétrica y reconocimiento quiral.

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