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Acoplamiento cruzado de ésteres de boro y carbonatos alilicos

Hong-Cheng Shen¹, Ze-Shu Wang¹, Adam Noble¹

¹School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.

Journal of the American Chemical Society

|May 9, 2024

Resumen

Este estudio introduce un método de acoplamiento cruzado catalizado por iridio controlado estereocontrolado para crear enlaces carbono-carbono. La técnica une eficientemente los ésteres borónicos enriquecidos con enantio con carbonatos alilicos, controlando la estereoquímica en moléculas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis estereoselectiva

Sus antecedentes:

La creciente demanda de moléculas tridimensionales complejas requiere métodos eficientes para formar enlaces carbono-carbono.
La construcción de enlaces C ((sp3) -C ((sp3) presenta desafíos significativos, particularmente con respecto al control estereocímico.
Los métodos de acoplamiento cruzado existentes a menudo luchan con la estereoselectividad al formar enlaces C ((sp3) -C ((sp3).

Objetivo del estudio:

Desarrollar una reacción de acoplamiento cruzado estereocontrolada para forjar enlaces C ((sp3) -C ((sp3).
Para permitir la síntesis de moléculas con centros estereogénicos únicos o vecinos.
Proporcionar un método para la síntesis estereodivergente de fragmentos de C ((sp3) acoplados.

Principales métodos:

Se utilizó la catálisis de iridio para la reacción de acoplamiento cruzado.
Utilizan ésteres borónicos enriquecidos con enantio como socios de acoplamiento nucleófilo.
Los ésteres borónicos reaccionados con carbonatos alilicos racémicos como socios electrófilos.

Principales resultados:

Se logró con éxito la formación estereocontrolada de enlaces C ((sp3) -C ((sp3).
Amplio alcance de sustrato demostrado, incluidos los ésteres borónicos primarios, secundarios y terciarios.
Permitió la preparación de los cuatro posibles estereoisómeros para productos con centros quirales vecinos.

Conclusiones:

El método desarrollado ofrece una solución novedosa para el acoplamiento estereodivergente de dos fragmentos C ((sp3).
Combina la reacción simultánea enantiospecífica de un nucleófilo quiral con la reacción enantioselectiva de un electrófilo quiral.
Avanza significativamente la síntesis de moléculas definidas estereoquímicamente con enlaces C ((sp3) -C ((sp3).

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