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Acoplamiento cruzado dirigido por hidroxilo: una síntesis escalable de Debromohamigeran E y otros objetivos de

Thomas P Blaisdell¹, James P Morken¹

¹Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States.

Journal of the American Chemical Society

|July 1, 2015

Resumen

Un grupo hidroxilo dirige las reacciones de acoplamiento cruzado catalizadas por paladio mediante la activación de boronatos de pinacol cercanos. Esto permite un control preciso de los sitios de reacción en moléculas complejas, incluso con boronatos no reactivos.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis por catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

Las reacciones de acoplamiento cruzado catalizadas por paladio son fundamentales en la síntesis orgánica.
El control de la regioselectividad en reacciones con sustratos multifuncionalizados sigue siendo un desafío.
Los boronatos de pinacol son versátiles intermediarios sintéticos.

Objetivo del estudio:

Investigar el efecto directivo de un grupo β-hidroxilo en las reacciones de acoplamiento cruzado catalizadas por paladio.
Demostrar la utilidad de este grupo de dirección para la funcionalización regioselectiva.
Para activar boronatos de pinacol que de otro modo no reaccionarían.

Principales métodos:

Reacciones de acoplamiento cruzado Suzuki-Miyaura catalizadas por el paladio.
Síntesis de sustratos con funcionalidades de β-hidroxilo y boronato de pinacol.
Análisis de los productos de reacción utilizando espectroscopia de RMN y espectrometría de masas.

Principales resultados:

El grupo β-hidroxilo dirigió efectivamente el acoplamiento cruzado catalizado por el paladio a la posición adyacente.
La regioselectividad se logró en sustratos que contienen múltiples grupos de boronato.
Los boronatos adyacentes al grupo hidroxilo mostraron una mayor reactividad.

Conclusiones:

Un grupo β-hidroxilo sirve como un grupo directivo efectivo en las reacciones de acoplamiento cruzado catalizadas por paladio.
Esta estrategia proporciona una poderosa herramienta para la síntesis regioselectiva y la activación de los boronatos.
Los hallazgos amplían el alcance de las reacciones catalizadas por el paladio y la química del boronato.

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