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Un sistema de catalizador general y eficiente para una oxidación de tipo Wacker utilizando TBHP como oxidante
Brian W Michel1, Andrew M Camelio, Candace N Cornell
1Department of Chemistry, University of Utah, 315 S 1400 E, Salt Lake City, Utah 84112-085, USA.
Journal of the American Chemical Society
|April 15, 2009
Resumen
Una nueva oxidación de tipo Wacker convierte eficientemente los alcoholes alilicos protegidos en productos de aciloína utilizando un ligando de Quinox y hidroperoxido acuoso de tert-butilo (TBHP). Este sistema catalítico escalable también oxida las olefinas a cetonas de metilo con alta enantioselectividad.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Reacciones de oxidación Reacciones de oxidación.
Sus antecedentes:
- Los alcoholes alelicos protegidos son sustratos desafiantes para los métodos de oxidación tradicionales.
- La oxidación del tipo Wacker normalmente requiere condiciones específicas y sistemas de catalizadores.
- El desarrollo de métodos de oxidación eficientes y generales es crucial en la química sintética.
Objetivo del estudio:
- Para desarrollar un nuevo protocolo de oxidación tipo Wacker.
- Para convertir eficientemente los alcoholes alilicos protegidos en productos de aciloína.
- Establecer un sistema catalítico general para varias oxidaciones de olefinas.
Principales métodos:
- Utilizó un ligando Quinox de síntesis rápida.
- Utilizó el hidroperoxido acuoso de tert-butilo (TBHP) disponible en el mercado como oxidante.
- Investigó el sistema catalítico para la oxidación de los alcoholes alelicos protegidos y las olefinas terminales.
Principales resultados:
- Se logró una conversión eficiente de los alcoholes alelicos protegidos a productos de aciloína.
- Generalidad demostrada para la conversión de olefinas terminales en metilcetonas en tiempos de reacción cortos.
- Se demostró la escalabilidad a 20 mmol con una carga de catalizador reducida (1 mol%).
- Se confirmó la retención completa del exceso enantiomérico para sustratos enriquecidos con enantio.
Conclusiones:
- La oxidación de tipo Wacker ligada a Quinox desarrollada es un método altamente eficiente y general.
- El protocolo ofrece una solución práctica para la síntesis de productos de aciloína a partir de sustratos difíciles.
- La escalabilidad del sistema y la alta enantioselectividad lo hacen valioso para aplicaciones sintéticas.
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