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Síntesis estereodivergente a través de la hidroboración inversa asimétrica catalítica
Tao-Tao Gao1, Wen-Wen Zhang1, Xin Sun1
1Center of Basic Molecular Science, Department of Chemistry , Tsinghua University , Beijing , 100084 , China.
Journal of the American Chemical Society
|February 27, 2019
Resumen
Los investigadores desarrollaron un método de hidroboración catalizado por Rh altamente selectivo para la síntesis orgánica. Este nuevo enfoque controla con precisión la estereoquímica, lo que permite una síntesis eficiente de moléculas quirales complejas para el descubrimiento de fármacos y la síntesis de productos naturales.
Área de la Ciencia:
- Síntesis orgánica
- Catálisis
- Estereoquímica
Sus antecedentes:
- El control de la quimio, regio, diastereo y enantioselectividad es crucial en la síntesis orgánica.
- La síntesis de todos los estereoisómeros de una molécula ayuda a la síntesis analógica de productos naturales y la creación de una biblioteca de compuestos quirales para el descubrimiento de fármacos.
- El control preciso de las configuraciones relativas y absolutas en la síntesis multiestereocéntrica sigue siendo un desafío en la catálisis asimétrica.
Objetivo del estudio:
- Desarrollar una nueva reacción de hidroboración controlada por catalizador.
- Para lograr una selectividad sin precedentes en la síntesis de moléculas con múltiples estereocentros.
- Proporcionar una estrategia versátil para la síntesis estereodivergente de bloques de construcción quirales.
Principales métodos:
- Hidroboración catalizada por Rh de compuestos carbonílicos α y β insaturados utilizando pinacolborano.
- Utilizando la geometría del sustrato (E o Z) y el enantiómero del ligando (S o R) para controlar los resultados estereoquímicos.
- Transformaciones estereospecíficas de los productos resultantes que contienen boro.
Principales resultados:
- La reacción de hidroboración se produjo con altas regioselectividades, diastereoselectividades y enantioselectividades.
- Se generaron con éxito dos estereocentros vecinos en los productos de hidroboración.
- Todos los diastereoisómeros posibles fueron fácilmente accesibles ajustando el sustrato y el ligando.
- Los productos que contienen boro se convirtieron en diversos bloques quirales a través de reacciones estereospecíficas.
Conclusiones:
- Se ha desarrollado una hidroboración altamente selectiva controlada por catalizador.
- Este método ofrece un control preciso sobre múltiples estereocentros, abordando un desafío clave en la síntesis asimétrica.
- La estrategia permite una síntesis eficiente y estereodivergente de compuestos quirales valiosos.
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