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Monohidrogenación asimétrica regioselectiva catalizada por iridio de 1,4-Dienos

Jianguo Liu¹, Suppachai Krajangsri¹, Thishana Singh¹

¹Department of Organic Chemistry, Stockholm University, Arrhenius-laboratory , 10691, Stockholm, Sweden.

Journal of the American Chemical Society

|September 21, 2017

Resumen

Los investigadores desarrollaron un nuevo catalizador de iridio para la monohidrogenación altamente eficiente de 1,4-dienes. Este método logra una excelente regioselectividad y enantioselectividad en condiciones suaves, ampliando las posibilidades sintéticas.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Los 1,4-dienos son productos intermedios sintéticos muy versátiles.
La hidrogenación asimétrica eficiente es crucial para producir compuestos enantioméricamente puros.

Objetivo del estudio:

Desarrollar un método altamente eficiente para la monohidrogenación regioselectiva y enantioselectiva de 1,4-dienos.
Explorar el alcance del sustrato del sistema catalítico desarrollado.

Principales métodos:

Utilizó un catalizador de iridio coordinado con un ligando quiral N,P.
Reacciones de monohidrogenación realizadas en condiciones suaves.
Investigó una variedad de sustratos de 1,4-dieno no funcionalizados y funcionalizados.

Principales resultados:

Se ha logrado una monohidrogenación regioselectiva y enantioselectiva altamente eficiente de 1,4-dienos.
Se ha demostrado una excelente regioselectividad y un exceso enantiomérico (hasta el 98% ee) para sustratos funcionalizados, incluidos los con alcoholes y cetalos protegidos por sililo.
Confirmado amplio alcance del sustrato, acomodando sustituyentes en meta- o para-posiciones.

Conclusiones:

El sistema catalizado por iridio desarrollado proporciona una herramienta poderosa para la monohidrogenación asimétrica de 1,4-dienos.
El método es eficaz para sustratos complejos, ofreciendo una alta selectividad y rendimiento.
Este avance tiene implicaciones significativas para la síntesis de moléculas quirales.

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