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Reacciones de acoplamiento cruzado de silanolatos aromáticos y heteroaromáticos con haluros aromáticos y
Scott E Denmark1, Russell C Smith, Wen-Tau T Chang
1Roger Adams Laboratory, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA. sdenmark@illinois.edu
Journal of the American Chemical Society
|February 10, 2009
Resumen
Los silanolatos de metales alcalinos permiten una síntesis eficiente de biarilo a través del acoplamiento cruzado catalizado por paladio. Este método, que utiliza bis ((tri-tert-butylphosphine) palladio, es eficaz para diversos sustratos y grupos funcionales.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Las reacciones de acoplamiento cruzado son vitales para la formación de enlaces C-C.
- Desarrollar métodos de acoplamiento eficientes y suaves sigue siendo un desafío clave.
Objetivo del estudio:
- Desarrollar un nuevo método de acoplamiento cruzado para la síntesis de polysubstituidos biaryls.
- Para explorar la utilidad de los silanolatos de metales alcalinos como socios de acoplamiento.
Principales métodos:
- Utilizando sales de metales alcalinos (potasio, sodio) de arilosilanolos y heteroarilosilanolos.
- Utilizando el paladio bis ((tri-tert-butilofosfina) como catalizador.
- Reaccionan los silanolatos con bromuros y cloruros aromáticos bajo condiciones suaves.
Principales resultados:
- Se logró una síntesis eficiente de biarilos polisubstituidos.
- Amplio alcance del sustrato que incluye arilsilanolatos ricos en electrones, pobres en electrones y estéricamente obstaculizados.
- Se observó una alta tolerancia al grupo funcional (ésteres, cetonas, éteres, etc.). En el caso de las personas que se encuentran en situación de exclusión social.
- Acoplamiento exitoso de sustratos difíciles como el (2-benzofuranilo) dimetilsilanolato y el (2,6-diclorofenilo) dimetilsilanolato.
Conclusiones:
- El método desarrollado ofrece una ruta versátil y eficiente a los compuestos biarílicos.
- El bis ((tri-tert-butylphosphine) paladio es crucial para el éxito y el alcance de la reacción.
- También se presentan métodos generales para sintetizar silanoles aromáticos.
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