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Resolución cinética dinámica de los atropisómeros de biarilo a través de la brominación asimétrica catalizada por

Jeffrey L Gustafson¹, Daniel Lim, Scott J Miller

¹Department of Chemistry, Yale University, 225 Prospect Street, Post Office Box 208107, New Haven, CT 06520-8107, USA.

Science (New York, N.Y.)

|June 5, 2010

Resumen

Este estudio introduce un nuevo catalizador tripeptídico para la resolución dinámica cinética de compuestos biarílicos. Este método permite la síntesis asimétrica eficiente de ligandos biarílicos atropisoméricos con alta enantioselectividad.

Área de la Ciencia:

Química orgánica es la química orgánica.
Síntesis asimétrica de síntesis.
La catálisis es la catálisis.

Sus antecedentes:

Los compuestos biarílicos axialmente quirales son cruciales en la síntesis moderna y se encuentran en productos naturales.
Los métodos de síntesis asimétrica directa para los biarilos atropisoméricos siguen siendo limitados.

Objetivo del estudio:

Desarrollar un método catalítico para la preparación asimétrica directa de compuestos biarílicos atropisoméricos.
Para lograr una resolución cinética dinámica de sustratos biarílicos racémicos utilizando un catalizador de moléculas pequeñas.

Principales métodos:

Utilizó un catalizador de moléculas pequeñas derivado de tripeptidos.
Se empleó una reacción de sustitución aromática electrofílica atropisómero selectiva.
Se utilizaron reactivos simples de brominación para la transformación.

Principales resultados:

Se ha logrado la síntesis enantioselectiva de compuestos biarílicos quirales no racémicos.
Se obtiene una excelente pureza óptica (a menudo >95:5 relación de enantiómeros).
Se informó de buenos rendimientos químicos aislados que oscilan entre el 65% y el 87%.

Conclusiones:

El catalizador tripeptídico media efectivamente la resolución cinética dinámica de los sustratos biarílicos.
Este trabajo proporciona una nueva ruta para la síntesis eficiente de valiosos compuestos biarílicos atropisoméricos.
Se ha propuesto un modelo mecanicista que explique la selectividad observada.

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