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Cicloadición enantioselectiva catalizada Ni-Al de carboxamida de ciclopropilo con alquina

Qi-Sheng Liu¹, De-Yin Wang¹, Zhi-Jun Yang¹

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

Journal of the American Chemical Society

|December 6, 2017

Resumen

Un nuevo catalizador bimetálico de níquel y aluminio permite reacciones de cicloadición enantioselectivas. Este método rompe eficientemente los enlaces C-C del ciclopropano, obteniendo valiosas carboxamidas de ciclopentenilo de alta pureza.

Área de la Ciencia:

Química organometálica
Catálisis asimétrica
Síntesis orgánica

Sus antecedentes:

Las reacciones de cicloadición son fundamentales en la síntesis orgánica.
La activación del enlace C-C del ciclopropano sigue siendo un reto.
La síntesis enantioselectiva es crucial para los productos farmacéuticos.

Objetivo del estudio:

Desarrollar una reacción de cicloadición enantioselectiva utilizando carboxamidas y alquinas de ciclopropilo.
Para explorar la utilidad de la catálisis bimetálica Ni-Al para la escisión de enlaces C-C.
Para sintetizar los nuevos ciclopentenil carboxamidas con un alto control estereoquímico.

Principales métodos:

Utilizó un sistema de catalizador bimetálico Ni-Al.
Se empleó un ligando bifuncional para permitir la catálisis.
Investigó la reacción entre las carboxamidas de ciclopropilo y varios alquinos.

Principales resultados:

Se obtienen altos rendimientos de carboxamidas ciclopentenilo (hasta el 99%).
Se obtienen productos con una enantioselectividad excelente (hasta el 94% ee).
Demostró la eficiencia del catalizador en la escisión de enlaces C-C no reactivos de ciclopropano.

Conclusiones:

La catálisis bimetálica Ni-Al es una estrategia poderosa para las cicloadiciones enantioselectivas.
El método desarrollado proporciona acceso a valiosas carboxamidas quirales de ciclopentenilo.
La catálisis bifuncional habilitada por ligandos supera los desafíos en la activación del ciclopropano.

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