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Los ftalidos por hidroacilación de cetonas catalizadas por el rodio
Diem H T Phan1, Byoungmoo Kim, Vy M Dong
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
Journal of the American Chemical Society
|October 10, 2009
Resumen
Los investigadores desarrollaron un nuevo método atómico-económico para sintetizar ftalidos utilizando la hidroacilación de cetonas enantioselectivas. Este enfoque produce productos de ftalido con alta enantioselectividad, ofreciendo un avance significativo en la síntesis orgánica.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis asimétrica de síntesis.
- La catálisis es la catálisis.
Sus antecedentes:
- Los ftalidos son lactonas de cinco miembros con una relevancia biológica significativa, que se encuentran naturalmente en varias fuentes vegetales.
- Los métodos sintéticos existentes para los ftalidos pueden carecer de economía atómica o de un control enantioselectivo eficiente.
Objetivo del estudio:
- Introducir el primer método atómico-económico para la síntesis de ftalidos.
- Para lograr una alta enantioselectividad en la producción de ftalidos a través de la hidroacilación intramolecular de cetonas.
- Investigar la influencia de los contraiones en el rendimiento catalítico.
Principales métodos:
- Se empleó la hidroacilación enantioselectiva intramolecular de cetonas utilizando un catalizador de rodio con un ligando de Duanphos.
- Utilizó varios 2-cetobenzaldehídos como sustratos.
- Se han investigado diferentes counteriones (NO3, OTf, OMs) para el complejo de rodio.
Principales resultados:
- Logró buenos rendimientos de productos de ftalidos.
- Se han demostrado altas enantioselectividades, que oscilan entre el 92% y el 98% ee.
- Identificó el papel crucial de los contreriones en la modulación de la reactividad y la enantioselectividad.
- Se realizó con éxito una síntesis total asimétrica concisa y concisa de (S) - (((-) -3-n-butilftalida.
Conclusiones:
- La hidroacilación de cetonas enantioselectiva desarrollada es una ruta eficiente y atómica-económica a los ftalidos.
- La selección de contrarios es fundamental para optimizar el proceso catalítico.
- Esta metodología proporciona una herramienta valiosa para acceder a ftalidos enriquecidos enantioméricamente, incluidos los productos naturales.
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