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Hidrogenación enantioselectiva catalizada por iridio de los ácidos carboxílicos alfa y beta insaturados

Shen Li¹, Shou-Fei Zhu, Can-Ming Zhang

¹State Key Laboratory and Institute of Elemento-organic Chemistry, Nankai University, Tianjin 300071, China.

Journal of the American Chemical Society

|June 13, 2008

Resumen

Un nuevo método de hidrogenación catalizado por iridio produce eficientemente ácidos carboxílicos quirales a partir de ácidos insaturados. Este avance utiliza nuevos ligandos de espiro-fosfino-oxazolina para una alta selectividad y reactividad.

Área de la Ciencia:

Química orgánica es la química orgánica.
Catalización asimétrica por catálisis asimétrica.
Química verde es la química verde.

Sus antecedentes:

Los ácidos carboxílicos quirales son bloques de construcción vitales en productos farmacéuticos y productos químicos finos.
El desarrollo de métodos eficientes de hidrogenación asimétrica es crucial para la síntesis sostenible.
Los métodos existentes a menudo se enfrentan a desafíos con el alcance del sustrato o la eficiencia del catalizador.

Objetivo del estudio:

Desarrollar una hidrogenación asimétrica altamente eficiente catalizada por iridio de ácidos carboxílicos alfa, beta insaturados.
Para lograr altas enantioselectividades y reactividades utilizando nuevos ligandos quirales.
Para sintetizar valiosos ácidos carboxílicos quirales sustituidos por alfa.

Principales métodos:

Se utilizaron complejos de iridio coordinados con ligandos quirales de espiro-fosfino-oxazolina.
Se realizó la hidrogenación de varios ácidos carboxílicos alfa, beta insaturados bajo condiciones optimizadas.
Caracterizó los productos utilizando técnicas analíticas estándar (NMR, HPLC).

Principales resultados:

Se logró una hidrogenación altamente eficiente con excelentes rendimientos.
Se obtienen ácidos carboxílicos quirales sustituidos por alfa en enantioselectividades excepcionalmente altas (hasta el 99% ee).
Demostrado amplio alcance de sustrato y altos números de rotación de catalizadores.

Conclusiones:

Desarrolló un robusto y eficiente protocolo de hidrogenación asimétrica catalizada por iridio.
Los ligandos quirales espiro-fosfino-oxazolina son muy eficaces para esta transformación.
Este método proporciona una valiosa ruta a los ácidos carboxílicos quirales enantioméricamente puros sustituidos por alfa.

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