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π-Coordinación de la catálisis sinérgica quiral de aminas primarias y paladio para la alquilación alilica asimétrica
Yaning Wang1,2, Junli Chai3, Chang You4
1Key Laboratory for Molecular Recognition and Function , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.
Journal of the American Chemical Society
|January 18, 2020
Resumen
Una nueva amina primaria quiral actúa como un catalizador y ligando dual, permitiendo la alquilación asimétrica catalizada por el paladio. Este enfoque crea eficientemente moléculas complejas con alta selectividad, ofreciendo acceso a ambos enantiómeros.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Síntesis asimétrica
Sus antecedentes:
- Las aminas primarias quirales son catalizadores y ligandos versátiles en la síntesis orgánica.
- La alquilación asimétrica catalizada por paladio es un método crucial para la formación de enlaces carbono-carbono.
- El desarrollo de catalizadores que controlen la estereoquímica y las velocidades de reacción es esencial para una síntesis eficiente.
Objetivo del estudio:
- Desarrollar una nueva amina primaria quiral que contenga areno como un aminocatalizador y un ligando duales.
- Investigar su catálisis sinérgica con el paladio para la alquilación alilica asimétrica.
- Lograr una alta eficiencia y selectividad en la creación de estereocentros cuaternarios todo carbono acíclicos.
Principales métodos:
- Utilizando una amina primaria quiral que contiene areno como un doble catalizador y ligando.
- Utilizando la catálisis sinérgica del paladio para la alquilación alilica asimétrica de los β-cetocarbonilos α-branqueados.
- Realización de estudios mecanicistas para aclarar la vía catalítica y el modo de coordinación.
Principales resultados:
- La amina primaria quiral que contiene areno demostró tasas de reacción mejoradas y inducción quiral inversa en comparación con su derivado voluminoso.
- Se logró una alta eficiencia y una excelente regioselectividad, estereo selectividad y enantioselectividad en la formación de estereocentros cuaternarios de carbono.
- Ambos enantiómeros de los productos fueron accesibles utilizando el mismo aminocatalizador quiral configurado.
- Se identificó un modo distintivo de coordinación Pd-areno como clave para una catálisis efectiva.
Conclusiones:
- La amina primaria quiral coordinadora π desarrollada es un catalizador dual y ligando eficaz para la alquilación alilica asimétrica.
- Este método proporciona acceso a bloques de construcción quirales valiosos con control sobre la estereoquímica.
- El catalizador muestra una amplia aplicabilidad en reacciones de alilación asimétricas que involucran varios sustratos.
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