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Acoplamiento cruzado Suzuki-Miyaura de carbamatos de arilo y sulfatos: estudios experimentales y computacionales
Kyle W Quasdorf1, Aurora Antoft-Finch, Peng Liu
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
Journal of the American Chemical Society
|April 5, 2011
Resumen
Este estudio introduce las primeras reacciones de acoplamiento cruzado Suzuki-Miyaura utilizando O-carbamatos de arilo y O-sulfamatos. Este método versátil sintetiza eficientemente los biarilos utilizando un catalizador de níquel de bajo costo.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- El acoplamiento cruzado Suzuki-Miyaura es una piedra angular de la síntesis orgánica moderna.
- Los O-carbamatos de arilo y los O-sulfamatos son grupos funcionales sintéticamente versátiles.
- El desarrollo de nuevos socios de acoplamiento para reacciones de acoplamiento cruzado sigue siendo un área activa de investigación.
Objetivo del estudio:
- Describir las primeras reacciones de acoplamiento cruzado Suzuki-Miyaura que involucran aril O-carbamato y O-sulfamato.
- Para demostrar el amplio alcance y la utilidad de esta nueva metodología.
- Para dilucidar el ciclo catalítico y comprender el mecanismo de reacción a través de estudios computacionales.
Principales métodos:
- Utilizado catalizador de níquel NiCl2 (((PCy3) 2 para reacciones de acoplamiento cruzado.
- Empleado arilo O-carbamatos y O-sulfamatos como socios de acoplamiento.
- Realizó un estudio computacional para investigar el ciclo catalítico y los estados de transición.
Principales resultados:
- Se obtienen buenos a excelentes rendimientos de los productos de biarilo.
- Tolerancia demostrada para una amplia gama de sustratos, incluidos los donantes de electrones, los recolectores de electrones y los grupos arilo orto-sustituidos.
- Demostró la aplicabilidad a sustratos heteroarilicos.
- Identificó un estado de transición de cinco centros para la adición oxidativa, lo que lleva a la esclusiva escisión de enlaces arilo C-O.
- Racionalizó el efecto del agua en la estabilidad del catalizador y las velocidades de reacción.
Conclusiones:
- Estableció una novedosa y eficiente metodología de acoplamiento cruzado Suzuki-Miyaura utilizando O-carbamatos de arilo y O-sulfamatos.
- El método ofrece una ruta versátil a los compuestos aromáticos polisubstituidos.
- Los hallazgos tienen implicaciones significativas para la síntesis de productos naturales y moléculas bioactivas.
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