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Catalizado por iridio [2 + 2 + 2] cicloadición de α,ω-diynes con nitriles

Gen Onodera¹, Yoshihisa Shimizu, Jun-na Kimura

¹Department of Chemistry and Biological Science, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo, Sagamihara, Kanagawa 252-5258, Japan.

Journal of the American Chemical Society

|May 19, 2012

Resumen

Este estudio introduce una eficiente cicloadición catalizada por iridio de dienas y nitriles para sintetizar piridinas. Este método es versátil, funciona con diversos nitriles y permite la creación de moléculas complejas como las terpiridinas.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Síntesis orgánica La síntesis orgánica.
La catálisis es la catálisis.

Sus antecedentes:

Las piridinas son compuestos heterocíclicos cruciales con amplias aplicaciones.
La síntesis eficiente de piridinas sustituidas sigue siendo un desafío clave en la química orgánica.

Objetivo del estudio:

Desarrollar un nuevo sistema catalítico para la síntesis de piridina.
Para explorar el alcance y las limitaciones de la reacción con varios sustratos.
Aplicar la metodología para construir sistemas aromáticos policíclicos complejos.

Principales métodos:

Reacción de cicloadición [4+2] catalizada por iridio entre α,ω-diinas y nitriles.
Utilizado [Ir(cod) Cl](2) / DPF o BINAP como el sistema catalítico.
Investigó la regioselectividad utilizando diinas asimétricas y empleó catalizadores quirales de difosfina para la síntesis enantioselectiva.

Principales resultados:

Logró una síntesis eficiente de piridinas a partir de una amplia gama de nitriles alifáticos y aromáticos.
Se ha demostrado una alta regioselectividad en la cicloadición de dienas no simétricas.
Sintetizó con éxito terpiridinas, quinquepiridinas y oligoheteroarenos en un solo paso.
Se obtienen piridinas quirales enriquecidas enantioméricamente a través de la resolución cinética con un 80% ee.

Conclusiones:

La cicloadición catalizada por iridio desarrollada ofrece una ruta versátil y eficiente a las piridinas y los heterociclos relacionados.
La metodología es aplicable a la síntesis de estructuras policíclicas complejas y derivados quirales de piridina.
El análisis computacional proporciona información sobre el mecanismo de reacción y la regioselectividad.

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