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Reorganizaciones asimétricas de claisen habilitadas por la síntesis catalítica asimétrica de Di (((allilo) éter

Scott G Nelson¹, Kan Wang

¹Department of Chemistry, University of Pittsburgh, Pennsylvania 15260, USA. sgnelson@pitt.edu

Journal of the American Chemical Society

|March 30, 2006

Resumen

Este estudio introduce un método de dos pasos que combina la síntesis asimétrica catalítica y la isomerización de olefinas-reorganización Claisen para reorganizaciones asimétricas alifáticas Claisen eficientes. El enfoque produce derivados altamente estereocontrolados de 2,3-disubstituidos de 4-pentenal, mostrando su utilidad sintética.

Área de la Ciencia:

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

Sus antecedentes:

Los reordenamientos alifáticos Claisen son cruciales para la síntesis de moléculas complejas.
Desarrollar métodos eficientes para los reordenamientos asimétricos alifáticos Claisen sigue siendo un desafío.

Objetivo del estudio:

Para establecer una ruta conveniente de dos pasos hacia los reordenamientos asimétricos alifáticos Claisen.
Para lograr un excelente estereocontrole relativo y absoluto en la síntesis de derivados 2,3-disubstituidos de 4-pentenal.

Principales métodos:

Síntesis asimétrica catalítica de los éteres di ((allyl).
Reacciones posteriores de isomerización de olefinas y reordenamiento de Claisen (ICR).

Principales resultados:

Combinación exitosa de la síntesis de di (((allil) éter y las reacciones ICR.
Altos rendimientos y un excelente estereocontrol (relativo y absoluto) de los derivados del pentenal objetivo.
Utilidad demostrada en la síntesis catalítica enantioselectiva del éter dimetilo (+) -calopina.

Conclusiones:

El protocolo de dos pasos desarrollado ofrece una vía práctica y eficiente para los reordenamientos asimétricos alifáticos Claisen.
Esta metodología es valiosa para las empresas de síntesis de moléculas complejas y de síntesis asimétrica.

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