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Monoariación selectiva mecanoquímica de los dibromoarenos imparciales por cristalización in situ
Tamae Seo1, Koji Kubota1,2, Hajime Ito1,2
1Division of Applied Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan.
Journal of the American Chemical Society
|April 28, 2020
Resumen
El acoplamiento mecanoquímico Suzuki-Miyaura de los dibromoarenos líquidos produce selectivamente productos monoarilados. Las transiciones de fase en estado sólido permiten transformaciones orgánicas selectivas difíciles en solución.
Área de la Ciencia:
- Química orgánica
- Ciencias de los materiales
- Ingeniería Química
Sus antecedentes:
- El acoplamiento cruzado Suzuki-Miyaura catalizado por el paladio es una herramienta sintética vital.
- El logro de la monoariación selectiva de los dibromoarenos imparciales es un desafío en los métodos basados en soluciones.
- La mecanoquímica ofrece condiciones de reacción alternativas con un potencial de selectividad único.
Objetivo del estudio:
- Investigar la monoarilación selectiva de dibromoarenos líquidos y no sesgados mediante el acoplamiento cruzado Suzuki-Miyaura catalizado por el paladio en condiciones mecanicas.
- Explorar el papel de las transiciones de fase en estado sólido en el control de la selectividad de la reacción.
- Demostrar un nuevo enfoque para las transformaciones orgánicas selectivas utilizando mecanoquímica.
Principales métodos:
- Moldeo mecanoquímico de bolas de dibromoarenos líquidos con ácidos arilborónicos y un catalizador de paladio.
- Monitoreo in situ del progreso de la reacción y de la formación del producto.
- Análisis de la selectividad del producto y la cinética de la reacción.
Principales resultados:
- La formación selectiva de productos monoarillados se logró en condiciones mecanicas.
- La menor reactividad de los productos monoarilados cristalinos, debido a la reducida eficiencia de difusión, se identificó como el factor clave para la selectividad.
- El estudio destaca el potencial de las transiciones de fase en estado sólido in situ para impulsar reacciones selectivas.
Conclusiones:
- El acoplamiento mecanoquímico Suzuki-Miyaura proporciona una nueva ruta para la monoariación selectiva de los dibromoarenos.
- El control de las transiciones de fase en estado sólido es una estrategia prometedora para el diseño de transformaciones orgánicas selectivas.
- Este enfoque ofrece ventajas sobre la síntesis convencional basada en soluciones para reacciones selectivas específicas.
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