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Funcionalización enantioselectiva del alcohol C-H para la construcción de policetidos: desbloqueo de la economía de
Jiajie Feng1, Zachary A Kasun1, Michael J Krische1
1Department of Chemistry, University of Texas at Austin , Austin, Texas 78712, United States.
Journal of the American Chemical Society
|April 27, 2016
Resumen
Los nuevos métodos catalíticos convierten los alcoholes más bajos en alcoholes más altos, lo que permite un acoplamiento C-C eficiente. Este enfoque simplifica la síntesis, en particular para los productos naturales de policetida, reduciendo los pasos y protegiendo el uso en grupo.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Química sintética
Sus antecedentes:
- La conversión directa de alcoholes en alcoholes más altos es un desafío.
- Las adiciones clásicas de carbonilo requieren reactivos estequiométricos y pasos redox discretos.
- La modificación selectiva del sitio de los polioles a menudo requiere grupos de protección.
Objetivo del estudio:
- Desarrollar métodos catalíticos estereoselectivos y selectivos del sitio para la conversión directa de alcohol a alcohol más alto.
- Para fusionar las características de transferencia de hidrogenación y adición de carbonilo para el acoplamiento C-C.
- Demostrar la utilidad de estos métodos en la síntesis de productos naturales.
Principales métodos:
- Explotación de alcoholes y reactivos π-insaturados como pares redox.
- Utilizando la transferencia de hidrógeno para generar intermedios transitorios de carbonilo-organometal.
- Aprovechar la preferencia cinética para la deshidrogenación primaria del alcohol para la selectividad del sitio.
Principales resultados:
- Desarrollo exitoso de métodos catalíticos para el acoplamiento directo C-C de alcohol a alcohol más alto.
- Eliminación de reactivos organometálicos estequiométricos y pasos discretos de alcohol a carbonilo redox.
- Modificación selectiva del sitio de los glicosilos y polioles sin grupos protectores.
- Síntesis total simplificada de los productos naturales poliquetídicos de tipo I en un menor número de pasos.
Conclusiones:
- Los métodos catalíticos desarrollados ofrecen una vía eficiente y selectiva para sintetizar alcoholes más altos a partir de alcoholes más bajos.
- Estos métodos reducen significativamente los pasos sintéticos y evitan proteger grupos en la síntesis de moléculas complejas.
- El enfoque proporciona una herramienta poderosa para la síntesis total de los productos naturales de policetida.
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