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Una solución general para los ácidos borónicos inestables: acoplamiento cruzado de liberación lenta de boronatos MIDA
David M Knapp1, Eric P Gillis, Martin D Burke
1Roger Adams Lab, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|May 2, 2009
Resumen
Los ácidos borónicos inestables ahora se pueden almacenar y utilizar de manera efectiva. Un nuevo método los libera lentamente de los boronatos MIDA estables, lo que permite reacciones eficientes de acoplamiento cruzado para varias síntesis químicas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Química Medicinal La Química Medicinal es el campo de la Química Medicinal.
Sus antecedentes:
- Muchos derivados valiosos del ácido borónico, como los tipos 2-heterocíclicos, vinilo y ciclopropilo, exhiben una inestabilidad inherente.
- Esta inestabilidad restringe su utilidad práctica en entornos de laboratorio, limitando el almacenamiento en la bancada y obstaculizando la participación eficiente en reacciones de acoplamiento cruzado.
Objetivo del estudio:
- Desarrollar un método general y robusto para superar la inestabilidad de varios derivados del ácido borónico.
- Para transformar ácidos borónicos inestables en bloques de construcción estables y fácilmente utilizables para la síntesis orgánica.
Principales métodos:
- El estudio introduce un nuevo enfoque que implica la liberación lenta in situ de ácidos borónicos inestables.
- Esta liberación se logra a partir de sus correspondientes precursores de boronato de ácido N-metilminodiacético (MIDA), que son estables en el aire.
Principales resultados:
- El método desarrollado estabiliza con éxito tres clases de ácidos borónicos previamente inestables: derivados 2-heterocíclicos, vinilo y ciclopropilo.
- Estos ácidos borónicos estabilizados, generados in situ a partir de boronatos MIDA, funcionan como bloques de construcción altamente efectivos.
- Demuestran capacidades eficientes de acoplamiento cruzado con una amplia gama de cloruros de arilo y heteroarilo.
Conclusiones:
- La estrategia de liberación lenta in situ de los boronatos MIDA proporciona una solución general para el manejo de ácidos borónicos inestables.
- Este enfoque mejora significativamente la accesibilidad y la utilidad de estos importantes intermedios sintéticos.
- El método amplía el alcance de las reacciones de acoplamiento cruzado que involucran sustratos de ácido borónico desafiantes.
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