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Acoplamiento estereospecífico de ésteres de boro con compuestos N-heteroaromáticos
Josep Llaveria1, Daniele Leonori2, Varinder K Aggarwal1
1School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K.
Journal of the American Chemical Society
|August 22, 2015
Resumen
Este estudio introduce un nuevo método de acoplamiento estereospecífico para los ésteres borónicos quirales y los heteroaromáticos N. El proceso eficiente produce productos de alta pureza enantiomérica, lo que hace avanzar la química orgánica sintética.
Área de la Ciencia:
- Química orgánica
- Química sintética
Sus antecedentes:
- Los ésteres borónicos quirales son valiosos intermedios sintéticos.
- Los N-heteroaromáticos son frecuentes en productos farmacéuticos y materiales.
- Se necesitan métodos eficientes para acoplar estos motivos.
Objetivo del estudio:
- Desarrollar un protocolo estereospecífico para el acoplamiento de ésteres borónicos quirales secundarios y terciarios con heteroaromáticos N-litiados.
- Para lograr una alta enantioselectividad en la reacción de acoplamiento.
Principales métodos:
- El protocolo implica la formación de un complejo de boronato.
- La activación del átomo de nitrógeno utilizando Troc-Cl induce una migración de 1,2.
- El proceso oxidativo se utiliza para obtener el producto final.
Principales resultados:
- El protocolo descrito permite el acoplamiento estereospecífico de ésteres borónicos quirales con N-heteroaromáticos.
- La reacción continúa con un alto exceso de enantiómeros, superior al 98%.
Conclusiones:
- Se ha establecido un método novedoso y eficiente para sintetizar compuestos quirales N-heteroaromáticos complejos.
- El protocolo ofrece una ruta confiable hacia productos enriquecidos enantioméricamente, valiosos para el descubrimiento de fármacos y la ciencia de los materiales.
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