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Los triboronatos de bencilo: bloques de construcción para la formación de enlaces de carbono-carbono por medio de la

W Neil Palmer¹, Cayetana Zarate¹, Paul J Chirik¹

¹Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States.

Journal of the American Chemical Society

|February 4, 2017

Resumen

La funcionalización C-H quimioselectiva mediante catalizadores de níquel permite la síntesis de bloques de construcción de poliborón a partir de hidrocarburos. Una nueva reacción en tándem crea productos diastereopuros con estereocentros cuaternarios en una olla.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

El desarrollo de métodos eficientes para la formación de enlaces carbono-carbono es crucial en la síntesis orgánica.
La funcionalización directa de los enlaces C-H ofrece un enfoque más atómico-económico en comparación con los métodos tradicionales.
El acceso a moléculas complejas con múltiples estereocentros sigue siendo un desafío significativo.

Objetivo del estudio:

Desarrollar un método altamente diastereoselectivo para la formación de enlaces carbono-carbono.
Para permitir la síntesis de bloques de construcción de poliborón a partir de hidrocarburos simples.
Crear un procedimiento de un solo recipiente para generar productos diastereopuros con estereocentros cuaternarios.

Principales métodos:

Descubrimiento de catalizadores de níquel alfa-diamina para la triborilación quimioselectiva de enlaces bencílicos C ((sp3) -H.
Se utiliza el bis ((pinacolato) diboro (B2Pin2) para la reacción de triborilación.
Desarrolló un método de adición y alquilación de conjugados deborilativos.

Principales resultados:

Se ha logrado un acoplamiento en tándem altamente diastereoselectivo de benciltriboronatos, enoatos y haluros de alquilo.
Se ha demostrado una eficacia en la funcionalización C-H de los metilarenos y en la diborilación de los enlaces C-H bencílicos secundarios.
Se han generado con éxito productos diastereopuros que contienen estereocentros cuaternarios mediante un procedimiento de un solo recipiente.

Conclusiones:

La funcionalidad C-H catalizada por níquel desarrollada proporciona acceso directo a valiosos bloques de construcción de poliborón.
La combinación de la perborilación bencílica y la adición-alquilación del conjugado deborilativo ofrece una ruta eficiente a moléculas complejas.
Esta metodología avanza significativamente en la síntesis de compuestos orgánicos estereoquímicamente ricos.

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