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Complejos de ésteres borónicos secundarios como nucleófilos de tipo organometálico quiral para la síntesis asimétrica

Robin Larouche-Gauthier¹, Tim G Elford, Varinder K Aggarwal

¹School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.

Journal of the American Chemical Society

|September 24, 2011

Resumen

Los investigadores desarrollaron un nuevo nucleófilo quiral a partir de un éster borónico y un reactivo de arillitio. Este método permite la síntesis asimétrica, la conversión de enlaces de carbono-boro en varios nuevos enlaces con alto estereocontrol.

Área de la Ciencia:

Química orgánica es la química orgánica.
Síntesis asimétrica de síntesis.
Química organometálica Química orgánica de los metales.

Sus antecedentes:

Los reactivos organometálicos quirales son cruciales para la síntesis asimétrica.
El desarrollo de nuevos reactivos quirales estables y versátiles sigue siendo un área activa de investigación.

Objetivo del estudio:

Introducir un nuevo nucleófilo quiral derivado de ésteres borónicos secundarios.
Para demostrar la utilidad de este reactivo en la formación de enlaces estereoselectivos.

Principales métodos:

Reacción de un reactivo de arillitio con un éster borónico secundario para formar un complejo de boro-ateno.
Reacción posterior del complejo de boro-atato con varios electrófilos.

Principales resultados:

El complejo de boro-ato actúa como un nucleófilo quiral, reaccionando con electrófilos con la inversión de la estereoquímica.
Conversión exitosa del enlace carbono-boro en enlaces C-I, C-Br, C-Cl, C-N, C-O y C-C.
Logró niveles muy altos de control estéreo en todas las transformaciones.

Conclusiones:

Se ha desarrollado un nuevo reactivo quiral de tipo organometálico, configuralmente estable y fácilmente disponible.
Este método amplía el conjunto de herramientas para la síntesis orgánica asimétrica.
El enfoque ofrece una plataforma versátil para la síntesis estereoselectiva de moléculas complejas.

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