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La adición asimétrica catalizada por Pd (II) de los malonatos a las dihidroisoquinolinas

Naoki Sasamoto¹, Christian Dubs, Yoshitaka Hamashima

¹IMRAM, Tohoku University, Miyagi 980-8577, Japan.

Journal of the American Chemical Society

|October 26, 2006

Resumen

Los complejos de paladio quiral catalizan la adición eficiente de malonatos a las dihidroisoquinolinas, produciendo derivados de tetrahidroisoquinolina ópticamente activos con altos rendimientos y enantioselectividad. Este método permite la síntesis de diversos compuestos sustituidos en condiciones suaves.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Síntesis asimétrica de síntesis.

Sus antecedentes:

Las dihidroisoquinolinas son importantes andamios heterocíclicos.
El acceso a los derivados de tetrahidroisoquinolina sustituidos por C1 con alta enantiopuridad es sintéticamente desafiante.

Objetivo del estudio:

Desarrollar una adición asimétrica catalítica eficiente de los malonatos a las dihidroisoquinolinas.
Para sintetizar derivados de tetrahidroisoquinolina sustituidos por C1 ópticamente activos.

Principales métodos:

Utilizó complejos quirales de Palladio (II) como catalizadores.
Empleó malonatos como nucleófilos y dihidroisoquinolinas como electrófilos.
Condiciones de reacción optimizadas para la suavidad y la eficiencia, incluida la adición lenta de 2,3-dicloro-5,6-dician-1,4-benzoquinona (DDQ) para la generación intermedia in situ.

Principales resultados:

Se logró una adición asimétrica catalítica altamente eficiente de los malonatos a las dihidroisoquinolinas.
Se obtuvieron varios derivados de tetrahidroisoquinolina sustituidos por C1 ópticamente activos con un rendimiento de hasta el 98% y un exceso enantiomérico (ee) del 97%.
Reacciones adicionales deshidrogenativas exitosas demostradas, que muestran la versatilidad del sustrato.

Conclusiones:

Desarrolló un método robusto y eficiente para sintetizar tetrahidroisoquinolinas enriquecidas enantioméricamente.
El sistema catalítico es eficaz para sustratos con diversos patrones de sustitución.
La reacción se lleva a cabo en condiciones suaves con tiempos de reacción cortos.

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