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Acoplamiento estereodivergente de aldehídos y alquinos mediante catálisis sinérgica utilizando Rh y Amina de Jacobsen

Faben A Cruz¹, Vy M Dong¹

¹Department of Chemistry, University of California , Irvine, California 92697, United States.

Journal of the American Chemical Society

|January 12, 2017

Resumen

Este estudio introduce un acoplamiento enantioselectivo de aldehídos y alquinas, creando complejos estereocentros de carbono. Este método catalítico proporciona acceso a todos los estereoisómeros con alta selectividad.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis estereoselectiva

Sus antecedentes:

La generación de estereocentros de carbono cuaternario y terciario es un desafío.
El control de la estereoquímica en la formación de enlaces carbono-carbono es crucial para el descubrimiento de fármacos y la ciencia de los materiales.

Objetivo del estudio:

Desarrollar una nueva reacción de acoplamiento enantioselectivo entre aldehídos alfa ramificados y alquinas.
Para lograr un alto estereocontrole (enantio, diastereoselectividad) y regioselectividad en la formación de estereocentros cuaternarios y terciarios.

Principales métodos:

Se utilizó una combinación de un catalizador de rodio (Rh) y un organocatalizador.
Investigó las condiciones de reacción para optimizar la selectividad y el rendimiento.
Se emplean varios aldehídos α-branqueados y alquinas como sustratos.

Principales resultados:

Se ha logrado con éxito el acoplamiento enantioselectivo entre aldehídos alfa ramificados y alquinas.
Estereocentros de carbono cuaternario y terciario generados con alta enantio-, diastereoselectividad y regioselectividad.
Se ha demostrado el acceso a todos los estereoisómeros posibles ajustando el sistema catalizador.

Conclusiones:

El sistema catalítico desarrollado activa eficazmente los aldehídos y las alquinas para el acoplamiento estereoselectivo.
Esta metodología ofrece una poderosa estrategia para sintetizar moléculas complejas con múltiples estereocentros.
La capacidad de acceder a estereoisómeros divergentes y isómeros constitucionales amplía las posibilidades sintéticas.

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