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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Alineación coordinada de las moléculas en estructuras quirales metal-orgánicas
Seungkyu Lee1, Eugene A Kapustin1, Omar M Yaghi2
1Department of Chemistry, University of California, Berkeley, CA 94720, USA. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. Kavli Energy NanoSciences Institute, Berkeley, CA 94720, USA. Berkeley Global Science Institute, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|August 20, 2016
Resumen
Las estructuras quirales metal-orgánicas como MOF-520 alinean con precisión las moléculas para la determinación de la estructura a través de la difracción de rayos X. Este método asigna de manera inequívoca configuraciones absolutas, incluso para moléculas complejas como las giberellinas.
Área de la Ciencia:
- La cristalografía
- Ciencias de los materiales
- Química orgánica
Sus antecedentes:
- Determinar la estructura 3D precisa y la configuración absoluta de las moléculas orgánicas es crucial en la química y el descubrimiento de fármacos.
- Los métodos tradicionales como la difracción de rayos X requieren cristales bien ordenados, que pueden ser difíciles de obtener para moléculas complejas o pequeñas.
- Los marcos quirales ofrecen potencial para la alineación molecular controlada y la cristalización enantioselectiva.
Objetivo del estudio:
- Investigar el uso de un marco quiral metal-orgánico (MOF-520) para la determinación de la estructura de diversas moléculas orgánicas.
- Para aprovechar el entorno quiral de MOF-520 para la asignación inequívoca de las configuraciones moleculares absolutas.
- Demostrar la capacidad del marco para cristalizar y caracterizar moléculas complejas, incluidos productos naturales y enantiómeros.
Principales métodos:
- Utilizó MOF-520 como material huésped para unir y alinear de manera coordinada las moléculas invitadas.
- Se emplearon técnicas de difracción de rayos X monocristalinos para determinar las estructuras de las moléculas huéspedes alineadas.
- Se aplicó la quiralidad intrínseca del MOF como referencia para la asignación de la configuración absoluta.
Principales resultados:
- Determinó con éxito las estructuras precisas de dieciséis moléculas diversas, incluidos alcoholes, fenoles, diolos y ácidos carboxílicos.
- Resolvió las estructuras de las hormonas vegetales complejas (gibberelinas), distinguiendo enlaces simples y dobles.
- Logró la cristalización enantioselectiva del ácido jasmónico racémico, determinando su configuración absoluta directamente.
Conclusiones:
- Los MOF quirales como el MOF-520 proporcionan una poderosa plataforma para la alineación molecular, facilitando la determinación de la estructura a través de la difracción de rayos X.
- Este método permite la asignación inequívoca de las configuraciones absolutas, superando las limitaciones de las técnicas tradicionales.
- La utilidad del marco se extiende a los productos naturales complejos y a la resolución enantioselectiva directa de las mezclas racémicas.
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