El grupo de ésteres remotos conduce a una resolución cinética eficiente de los alcoholes alifáticos racémicos a
Xiao-Hui Yang1, Ke Wang, Shou-Fei Zhu
1State Key Laboratory and Institute of Elemento-organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University , Tianjin 300071, China.
Journal of the American Chemical Society
|December 2, 2014
Resumen
Un nuevo método utiliza un catalizador de iridio quiral para una resolución cinética eficiente de los alcoholes racémicos. Este proceso respetuoso con el medio ambiente produce ésteres hidroxi quirales y diolos con alta enantioselectividad, incluso a muy bajas concentraciones de catalizador.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis por catálisis.
- Síntesis asimétrica de síntesis.
Sus antecedentes:
- La resolución cinética de los alcoholes racémicos es crucial para la síntesis de compuestos quirales.
- Los métodos existentes a menudo requieren condiciones duras o carecen de eficiencia.
- El desarrollo de métodos de resolución eficientes y respetuosos con el medio ambiente es un desafío continuo.
Objetivo del estudio:
- Desarrollar un método altamente eficiente para la resolución cinética de alcoholes alifáticos racémicos.
- Para lograr esto sin alterar el grupo hidroxilo.
- Para utilizar un nuevo sistema catalítico para la síntesis asimétrica.
Principales métodos:
- Empleando un complejo quiral de iridio como catalizador.
- Utilizando la hidrogenación mediada por grupo de éster remoto.
- Realización de la resolución cinética en alcoholes alifáticos racémicos.
Principales resultados:
- Se logró una resolución cinética altamente eficiente de los alcoholes alifáticos racémicos.
- Produjo ésteres quirales δ-alquilo-δ-hidroxi y δ-alquilo-1,5-diolos.
- Obtuvo buenos rendimientos y altas enantioselectividades.
- Eficacia demostrada a una carga de catalizador extremadamente baja (0,001 mol %).
Conclusiones:
- Se ha establecido un método poderoso y respetuoso con el medio ambiente para la resolución cinética de los alcoholes.
- El método ofrece alta eficiencia y enantioselectividad.
- Este enfoque es valioso para acceder a bloques de construcción quirales en la síntesis orgánica.
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