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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Observación directa de la preorganización molecular para la transferencia de quiralidad en la superficie de un
Vincent Demers-Carpentier1, Guillaume Goubert, Federico Masini
1Centre de recherche sur les propriétés des interfaces et la catalyse (CERPIC) and Département de chimie, Université Laval, Québec, QC G1V 0A6, Canada.
Science (New York, N.Y.)
|November 15, 2011
Resumen
Los catalizadores quirales permiten la síntesis asimétrica mediante el control de la estereoselectividad. Este estudio revela las interacciones moleculares precisas que rigen la transferencia de quiralidad en las superficies metálicas, avanzando la catálisis heterogénea asimétrica.
Área de la Ciencia:
- Química de las superficies.
- La catálisis es la catálisis.
- La estereoquímica es la estereoquímica.
Sus antecedentes:
- Los compuestos ópticamente activos en las superficies metálicas pueden crear sitios de transferencia de quiralidad catalíticamente activos.
- El mecanismo de estereoselectividad en la inducción asimétrica heterogénea es complejo y poco comprendido.
- Estudios previos carecían de resolución en un solo sitio para distinguir las conformaciones estereoquímicas.
Objetivo del estudio:
- Investigar el mecanismo de la inducción asimétrica heterogénea a nivel submolecular.
- Para revelar las fuerzas estereodireccionadoras que gobiernan las interacciones quirales modificador-sustrato en superficies metálicas.
- Demostrar la accesibilidad de la resolución de un solo sitio para el estudio de la catálisis asimétrica.
Principales métodos:
- Microscopía de túnel de barrido (STM) para imágenes submoleculares.
- Cálculos de la teoría funcional de la densidad (DFT) para conocimientos mecanicistas.
- Enfoque combinado STM-DFT para el análisis de superficies de alta resolución.
Principales resultados:
- Se identificaron complejos de superficie bimoleculares precisos de modificador quiral y sustrato.
- Reveló las fuerzas estereodireccionadoras que gobiernan la preorganización compleja.
- Se ha demostrado una conmutación proquiral inducida por un modificador quiral en la superficie.
- Se observaron relaciones procirales variables en diferentes sitios de unión submolecular.
Conclusiones:
- La inducción asimétrica heterogénea puede estudiarse con resolución en un solo sitio.
- La transferencia de quiralidad se rige por fuerzas intermoleculares específicas a nivel molecular.
- La comprensión de estas fuerzas permite el diseño racional de catalizadores asimétricos.
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