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Las reacciones de aza-Diels-Alder enantioselectivas (formales) con dienes de tipo no Danishefsky
Uttam K Tambar1, Sharon K Lee, James L Leighton
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Journal of the American Chemical Society
|July 29, 2010
Resumen
Los ácidos de Lewis de silicio quiral catalizan las reacciones aza-Diels-Alder enantioselectivas. Este método eficiente sintetiza diversas tetrahidropiridinas con alta enantioselectividad bajo condiciones suaves.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis asimétrica de síntesis.
Sus antecedentes:
- La reacción aza-Diels-Alder es una herramienta poderosa para construir heterociclos que contienen nitrógeno.
- El desarrollo de variantes enantioselectivas es crucial para acceder a moléculas quirales con actividad biológica.
Objetivo del estudio:
- Desarrollar una nueva reacción aza-Diels-Alder enantioselectiva formal.
- Para utilizar ácidos quirales de silicio Lewis simples y económicos para la catálisis.
- Para sintetizar una amplia gama de derivados de la tetrahidropiridina.
Principales métodos:
- Empleando acilhidrazonas (derivadas de glioxilato y aldehídos alifáticos) como socios de reacción.
- Utilizando dienes no de tipo Danishefsky en la reacción.
- Catálisis por un ácido de Lewis de silicio quiral bajo condiciones de temperatura ambiente.
Principales resultados:
- Desarrollo exitoso de reacciones formales aza-Diels-Alder enantioselectivas.
- Amplio alcance de sustrato, acomodando varias hidrazonas y dienes.
- Síntesis de diversas tetrahidropiridinas con buena o excelente enantioselectividad.
Conclusiones:
- El método desarrollado ofrece una ruta eficiente y económica a las tetrahidropiridinas enriquecidas enantioméricamente.
- El silicio quiral ácido de Lewis es eficaz para promover estas transformaciones.
- Este enfoque proporciona acceso a valiosos bloques de construcción quirales para futuras aplicaciones sintéticas.
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