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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Sobre la estabilidad de configuración absoluta de los iones de bromo y cloro
Scott E Denmark1, Matthew T Burk, Andrew J Hoover
1Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA. sdenmark@illinois.edu
Journal of the American Chemical Society
|January 12, 2010
Resumen
Los iones de bromonio y cloro definidos por configuración permiten la halofuncionalización enantioselectiva. Estos intermediarios clave mantienen una alta estereospecificidad durante la captura nucleofílica, incluso con olefinas competidoras presentes.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La estereoquímica es la estereoquímica.
- La catálisis es la catálisis.
Sus antecedentes:
- Los iones halonio son intermediarios esenciales en las reacciones de halogenación de alquenos y de halofuncionalización.
- Los métodos sintéticos existentes carecen de variantes enantioselectivas robustas debido a desafíos como la formación reversible de iones de halonio y la transferencia de olefinas.
Objetivo del estudio:
- Desarrollar un método para generar iones de bromo y cloro definidos configurativamente y enriquecidos enantioméricamente.
- Para investigar la estereospecificidad de la captura nucleofílica de estos iones halonio.
Principales métodos:
- Generación de iones de bromo y cloro enriquecidos enantioméricamente a través de la solvolisis de precursores quirales.
- Intercepción intermolecular de estos iones halonio con varios nucleófilos.
Principales resultados:
- Los iones de halonio enriquecidos enantioméricamente fueron generados con éxito e interceptados por nucleófilos con alta enantio- y diastereospecificidad.
- La estereospecificidad de la captura nucleofílica se mantuvo alta incluso en presencia de olefinas, superando un desafío clave.
Conclusiones:
- La funcionalización halo enantioselectiva catalítica se puede lograr utilizando iones de halonio definidos por configuración.
- Este enfoque proporciona una nueva y poderosa estrategia para la síntesis estereocontrolada que involucra alquenos.
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