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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Las reacciones radicales en las cavitandas revelan los efectos de la afinidad en los sistemas supramoleculares
Manuel Petroselli1,2, Venkatachalam Angamuthu1, Faiz-Ur Rahman1
1Center for Supramolecular Chemistry & Catalysis and Department of Chemistry, College of Science , Shanghai University , 99 Shang-Da Road , Shanghai 200444 , P. R. China.
Journal of the American Chemical Society
|January 9, 2020
Resumen
Los compuestos de contenedores solubles en agua facilitan la reducción radical de haluros de alquilo y la oxidación aeróbica de los aromáticos. Las altas afinidades de unión son cruciales para las reacciones dentro de estos sistemas supramoleculares dinámicos.
Área de la Ciencia:
- Química supramolecular
- Síntesis orgánica
- La Química Radical
Sus antecedentes:
- Los compuestos de contenedores ofrecen entornos únicos para las reacciones químicas.
- El control de la reactividad dentro de espacios confinados es un desafío clave en química.
Objetivo del estudio:
- Investigar el uso de compuestos contenedores solubles en agua para reacciones radicales.
- Establecer directrices para el empleo de sistemas supramoleculares dinámicos en la síntesis orgánica.
Principales métodos:
- Se utilizan cavitantes y huéspedes hidrosolubles (compuestos 1 y 2) como compuestos contenedores.
- Se realizó la reducción radical de varios α,ω-dihaluros utilizando iniciadores de radicales.
- Se analizaron las distribuciones de productos para comprender los mecanismos de reacción y los efectos de confinamiento.
Principales resultados:
- Se ha demostrado la reducción radical exitosa de haluros de alquilo dentro de los compuestos contenedores.
- Se ha demostrado la oxidación aeróbica de aromáticos alquilo utilizando los mismos sistemas.
- Se identificó un requisito crítico de altas afinidades de unión al sustrato huésped (Ka > 10^3 M^-1) para un confinamiento efectivo.
Conclusiones:
- Los compuestos contenedores solubles en agua pueden mediar efectivamente las reacciones radicales.
- Los sistemas supramoleculares dinámicos requieren una alta afinidad de sustrato para una reactividad controlada.
- Estos hallazgos proporcionan directrices para el diseño de sistemas supramoleculares para aplicaciones sintéticas.
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