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Reacción catalítica enantioselectiva Nitroso Diels-Alder

Biplab Maji¹, Hisashi Yamamoto¹

¹Molecular Catalyst Research Center, Chubu University , 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan.

Journal of the American Chemical Society

|November 27, 2015

Resumen

Este estudio introduce una nueva reacción asimétrica de nitroso Diels-Alder catalizada por el cobre. Este método sintetiza eficientemente moléculas orgánicas complejas con alta selectividad, útiles en el descubrimiento de fármacos.

Área de la Ciencia:

Química orgánica
Catálisis asimétrica
Metodología sintética

Sus antecedentes:

La reacción de nitroso Diels-Alder (NDA) es una herramienta valiosa para sintetizar compuestos heterocíclicos.
El desarrollo de variantes asimétricas de la reacción NDA es crucial para acceder a moléculas enantioméricamente puras.

Objetivo del estudio:

Desarrollar una reacción NDA intermolecular asimétrica catalizada por Cu(I) -DTBM-Segphos.
Para sintetizar 3,6-dihidro-1,2-oxazinas y derivados relacionados con alto estereocontrol.

Principales métodos:

Se utilizó un sistema de catalizador Cu ((I) -DTBM-Segphos.
Se utilizan compuestos reactivos de nitroso derivados de pirimidina y derivados de piridazina.
Reaccionó con varios 1,3-dienes cíclicos sustituidos.

Principales resultados:

Se han conseguido rendimientos elevados (hasta el 99%) para los conductos de carga cíclica.
Se ha demostrado una excelente regioselectividad (> 99:1) y enantioselectividad (> 99% ee).
Aplicó con éxito la metodología a la síntesis formal de conduramina A-1 y narciclasina.

Conclusiones:

El sistema catalítico desarrollado proporciona una ruta eficiente a moléculas quirales complejas.
Esta metodología amplía el alcance de las reacciones NDA asimétricas.
Permite el acceso a valiosos intermedios para la síntesis de productos naturales.

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