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Hidrogenación asimétrica altamente eficiente catalizada por iridio de ésteres de β-enamina no protegidos

Guohua Hou¹, Wei Li, Miaofeng Ma

¹Department of Chemistry and Chemical Biology & Pharmaceutical Chemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.

Journal of the American Chemical Society

|August 28, 2010

Resumen

Un nuevo método catalítico permite una hidrogenación eficiente y enantioselectiva de ésteres de β-enamina sin protección. Esto proporciona acceso directo a valiosos aminoácidos β-libres con alto rendimiento y excelente control estéreo.

Área de la Ciencia:

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

Sus antecedentes:

Los β-aminoácidos son bloques de construcción cruciales en productos farmacéuticos y moléculas biológicamente activas.
La síntesis eficiente de ácidos β-amino enantioméricamente puros sigue siendo un desafío significativo en la química orgánica.

Objetivo del estudio:

Desarrollar un método altamente eficiente y enantioselectivo para la síntesis de ácidos β-amino libres.
Para utilizar un nuevo catalizador de iridio para la hidrogenación directa de ésteres de β-enamina sin protección.

Principales métodos:

Desarrollo de un sistema catalítico utilizando un complejo de iridio con ligando (S,S) -f-Binaphane.
Hidrogenación de varios ésteres de beta-enamina sin protección bajo condiciones optimizadas.
Análisis del rendimiento del producto y el exceso enantiomérico (ee) utilizando cromatografía quiral.

Principales resultados:

Se logró una hidrogenación altamente eficiente y enantioselectiva de ésteres de β-enamina no protegidos.
Se obtienen ácidos β-amino libres de alto rendimiento (hasta 97% ee).
Se ha demostrado una alta actividad catalítica con números de facturación (TON) superiores a 5000.

Conclusiones:

La hidrogenación catalizada desarrollada de Ir-(S,S) -f-Binaphane es un método poderoso para sintetizar ácidos amino β enantiopuros.
Esta metodología ofrece una ruta directa y eficiente a valiosos bloques de construcción quirales.
La alta eficiencia y selectividad del catalizador abren nuevas vías para la síntesis farmacéutica.

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