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A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
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Catálisis ternaria habilitada de alquilación alilica asimétrica de tres componentes como una vía concisa a las
Zhenghui Kang1, Wenju Chang2, Xue Tian1
1Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
Journal of the American Chemical Society
|December 6, 2021
Resumen
Este estudio introduce una nueva reacción de alilación asimétrica de tres componentes para sintetizar cetonas quirales. El método crea eficientemente moléculas complejas utilizando un sistema catalítico cooperativo, avanzando en la síntesis asimétrica.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Síntesis asimétrica
Sus antecedentes:
- Las reacciones multicomponentes (MCR) son valiosas en la síntesis.
- Se establece la intercepción de ylidos de onium transitorios a través de las adiciones de Aldol, Mannich y Michael.
- Anteriormente no se conocía la intercepción asimétrica del tipo de sustitución catalítica de los ylidos de onio.
Objetivo del estudio:
- Desarrollar una nueva reacción de alilación asimétrica de tres componentes.
- Para lograr la intercepción asimétrica de tipo sustitución catalítica de los ylidos de onio.
- Para sintetizar las cetonas quirales α,α-disubstituidas.
Principales métodos:
- Utilizando un sistema ternario de catálisis cooperativa.
- Utilizando un complejo achiral Pd, Rh2 ((OAc) 4 y ácido fosfórico quiral (CPA).
- Compuestos α-diazocarbonílicos reactivos, alcoholes y carbonatos de alelo.
Principales resultados:
- Primer ejemplo de alquilación alilica asimétrica de tres componentes a través de un proceso de captura de tipo SN1.
- Conjunto convergente de especies de Pd-alilo y productos intermedios de enol.
- Acceso rápido a las cetonas quirales α,α-disubstituidas en buenos a altos rendimientos.
- Se obtiene una enantioselectividad de alta a excelente.
Conclusiones:
- El método desarrollado proporciona una ruta eficiente a las cetonas quirales α,α-disubstituidas.
- Los estudios experimentales y computacionales aclararon el mecanismo de reacción.
- Identificó el papel crucial del ligando Xantphos y el origen de la enantioselectividad.
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