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Nanorreactores basados en micelas con enlaces cruzados en la cáscara para la resolución cinética hidrolítica
1Molecular Design Institute and Department of Chemistry, New York University, New York, New York 10003-6688, USA.
Journal of the American Chemical Society
|August 18, 2011
Resumen
Las micelas reticuladas de la cáscara (SCM) con núcleos salinos de cobalto catalizan eficientemente la hidrólisis del epoxido. Estos nanoreactores exhiben una alta selectividad de sustrato y se pueden reutilizar durante ocho ciclos, lo que demuestra su estabilidad y potencial catalítico.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- La catálisis es la catálisis.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los copolímeros anfifílicos poli ((2-oxazolina) tribloqueantes son bloques de construcción efectivos para las nanoestructuras.
- Las micelas reticuladas de la cáscara (SCM) ofrecen propiedades únicas de nanorreactor para aplicaciones catalíticas.
- Los complejos cobalto-saleno son conocidos por su actividad catalítica en diversas transformaciones orgánicas.
Objetivo del estudio:
- Para sintetizar y caracterizar los SCM con núcleos de Co (III) -salina.
- Para investigar el rendimiento catalítico de estos SCM en la resolución cinética hidrolítica de los epoxidos terminales.
- Evaluar la reciclabilidad y estabilidad de los catalizadores SCM.
Principales métodos:
- Preparación de copolímeros anfifílicos poli ((2-oxazolina) tribloqueados. preparación de copolímeros anfifílicos poli ((2-oxazolina) tribloqueados.
- El autoensamblaje de copolímeros en SCM con núcleos de Co (III) -salen encapsulados.
- Resolución cinética de los epóxidos terminales mediante el uso de catalizadores SCM.
- La recuperación del catalizador a través de la ultrafiltración.
Principales resultados:
- Se han sintetizado con éxito SCMs que contienen núcleos de Co (III) -salen.
- Los catalizadores SCM demostraron una alta eficiencia catalítica para la hidrólisis del epoxido.
- Se observó una significativa selectividad del sustrato, correlacionada con la hidrofobidad del epoxido.
- Los catalizadores del nanorreactor se recuperaron y se reutilizaron durante ocho ciclos con actividad retenida.
Conclusiones:
- Los SCM sirven como nanorreactores efectivos para la resolución cinética catalítica de los epoxidos.
- Los catalizadores SCM de Co (III) -salen exhiben una selectividad de sustrato ajustable.
- La nanoescala y la estabilidad de los SCM permiten una eficiente recuperación y reutilización del catalizador.
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