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A Strategy for Sensitive, Large Scale Quantitative Metabolomics

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Reorganización asimétrica [2,3] de las ylidas de alil amonio derivadas de glicina

James A Workman¹, Neil P Garrido, Julien Sançon

¹School of Chemistry, University of Reading, Reading RG6 6AD, UK, and Hoffmann-La Roche, Ltd., Discovery Chemistry, 4070-Basel, Switzerland.

Journal of the American Chemical Society

|January 27, 2005

Resumen

Este estudio introduce reordenamientos [2,3]-sigmatrópicos altamente enantioselectivos para las ylidas acíclicas alílicas de amonio. El método sintetiza eficientemente las alliglicinas con excelente estereocontrol, lo que demuestra su utilidad en la síntesis orgánica.

Área de la Ciencia:

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

Sus antecedentes:

Las ylidas acíclicas alílicas de amonio acíclico son versátiles intermediarios en la síntesis orgánica.
El desarrollo de métodos enantioselectivos para su reordenamiento es crucial para acceder a los bloques de construcción quirales.

Objetivo del estudio:

Informar sobre los primeros ejemplos de reordenamientos sigmatrópicos [2,3]-sigmatrópicos altamente enantioselectivos de ylídeos acíclicos de amonio alilico.
Demostrar una síntesis rápida y eficiente de las alliglicinas con alto estereocontrol.

Principales métodos:

Se utilizan N-{2'-[(N'-allyl-N',N'-dialkyl) amonio]}sultamos de acetilcáforo como sustratos.
Reorganizaciones realizadas en una solución de 1,2-dimetoxietano (DME) a 0 grados C.
Empleó auxiliares quirales para lograr un alto control diastereofacial.

Principales resultados:

Se han logrado reorganizaciones sigmatrópicas [2,3]-enantioselectivas.
Se obtienen alilglicinas en rendimientos generalmente altos.
Se ha demostrado un alto control diastereofacial, con proporciones de hasta 99:1 de relación diastereomérica (dr).

Conclusiones:

Estableció un nuevo y poderoso método para la síntesis de alilglicinas quirales.
El reordenamiento desarrollado es eficiente y exhibe una excelente estereoselectividad.
Aplicó con éxito el método a una síntesis rápida de (R) -alil glicina.

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