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Síntesis de Olefinas Z-Selectivas a través del acoplamiento reductor catalizado por hierro de haluros de alquilo con

Chi Wai Cheung¹, Fedor E Zhurkin¹, Xile Hu¹

¹Laboratory of Inorganic Synthesis and Catalysis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ISIC-LSCI, BCH 3305, Lausanne 1015, Switzerland.

Journal of the American Chemical Society

|April 2, 2015

Resumen

Este estudio presenta un nuevo método catalítico para sintetizar las Z-olefinas, cruciales para los productos farmacéuticos. El acoplamiento cruzado reductor catalizado por hierro de haluros de alquilo y alquinas ofrece una alta selectividad y un amplio alcance de sustrato.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La síntesis selectiva de Z-olefinas sigue siendo un desafío significativo en la química orgánica.
Los métodos existentes a menudo requieren reactivos caros o tóxicos, lo que limita su aplicación práctica.

Objetivo del estudio:

Desarrollar un método novedoso, eficiente y rentable para la síntesis catalítica selectiva de Z-olefinas.
Explorar el alcance y las limitaciones de la estrategia sintética desarrollada.

Principales métodos:

Acoplamiento cruzado reductivo de haluros de alquilo con arylalquinos terminales.
Se utilizó un catalizador de bromuro de hierro (II) barato y un reductor de zinc.
Alcance de sustrato investigado que incluye haluros de alquilo primarios, secundarios y terciarios.

Principales resultados:

Se logra una alta selectividad Z en la síntesis de olefinas 1,2-disubstituidas.
Tolerancia demostrada a un amplio grupo funcional y alcance del sustrato.
Aplicó con éxito el método para sintetizar moléculas farmacéuticamente relevantes.

Conclusiones:

El acoplamiento cruzado reductor catalizado por hierro desarrollado proporciona una ruta robusta y selectiva a las Z-olefinas.
La reacción procede a través de una vía de carbocinación anti-selectiva, ofreciendo una visión mecanicista.
Este método presenta una herramienta valiosa para la construcción de moléculas orgánicas complejas, particularmente en la síntesis farmacéutica.

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