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Aminación alilica regioselectiva y enantioselectiva catalizada por cobalto
Samir Ghorai1, Sahadev Shrihari Chirke1, Wen-Bin Xu1
1Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering Shanghai Jiao Tong University , 800 Dongchuan Road , Shanghai 200240 , China.
Journal of the American Chemical Society
|July 6, 2019
Resumen
Una nueva reacción catalizada por cobalto permite la síntesis eficiente de valiosas aminas alilicas a partir de materiales de partida fácilmente disponibles. Este método logra altos rendimientos, una selectividad ramificada exclusiva y una excelente enantioselectividad en condiciones suaves.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Síntesis asimétrica
Sus antecedentes:
- Las aminas alilicas son bloques de construcción cruciales en productos farmacéuticos y naturales.
- El desarrollo de métodos eficientes y selectivos para su síntesis es de gran interés.
- Los métodos existentes a menudo se basan en catalizadores de metales preciosos o carecen de una alta enantioselectividad.
Objetivo del estudio:
- Desarrollar la primera aminación alilica enantioselectiva catalizada por cobalto abundante en la tierra.
- Para sintetizar aminas alilicas muy ramificadas a partir de carbonatos alilicos racémicos.
- Para lograr altos rendimientos, una selectividad ramificada y una excelente enantioselectividad.
Principales métodos:
- Utilizó un catalizador de cobalto con metales abundantes en la tierra.
- Se emplean carbonatos alilicos ramificados racémicos y varias aminas aromáticas/alifáticas.
- Condiciones de reacción optimizadas para la suavidad y la eficiencia.
Principales resultados:
- Logró la primera aminación alilica altamente ramificada y enantioselectiva catalizada por cobalto.
- Se obtienen aminas alilicas de alto rendimiento.
- Se ha demostrado una selectividad exclusivamente ramificada y unas enantioselectividades excelentes (normalmente del 99%).
Conclusiones:
- Desarrolló un método práctico y eficiente para sintetizar aminas alilicas enriquecidas enantioméricamente.
- El uso de cobalto abundante en la tierra ofrece una alternativa sostenible a los catalizadores de metales preciosos.
- Esta metodología proporciona un acceso rápido a bloques de construcción quirales valiosos.
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