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Arilcianamiento intramolecular de alceno catalizado por el níquel/AlMe2Cl

Yoshiaki Nakao¹, Shiro Ebata, Akira Yada

¹Department of Material Chemistry, Kyoto University, Kyoto, Japan. yoshiakinakao@npc05.mbox.media.kyoto-u.ac.jp

Journal of the American Chemical Society

|September 10, 2008

Resumen

Un nuevo catalizador basado en níquel permite la arilcianatión intramolecular de alquenos, produciendo eficientemente diversos nitriles con un carbono cuaternario bencílico. Este método ofrece nuevas vías para crear estereocentros cuaternarios quirales.

Área de la Ciencia:

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

Sus antecedentes:

La arilcianatión intramolecular es una transformación clave para la construcción de moléculas orgánicas complejas.
El desarrollo de sistemas catalíticos eficientes para la arilcianado sigue siendo un área activa de investigación.

Objetivo del estudio:

Desarrollar un nuevo sistema de níquel-cocatalizador para la arilcianado intramolecular de alquenos.
Investigar el alcance, el mecanismo y el potencial asimétrico de esta nueva reacción.

Principales métodos:

Utilizó un sistema de catalizador basado en níquel con cloruro de etilo de aluminio (AlMe2Cl) como cocatalizador.
Reacciones de arilcianado intramoleculares realizadas en varios sustratos de alqueno.
Se realizaron estudios mecanicistas y se exploró una variante asimétrica de la reacción.

Principales resultados:

Se ha logrado la exclusiva exo-dig ciclización, dando una amplia gama de nitriles.
Productos sintetizados que contienen un carbono cuaternario bencílico en buenos rendimientos.
El éxito preliminar demostrado en el desarrollo de una versión asimétrica para la síntesis quiral.

Conclusiones:

El sistema de níquel-cocatalizador desarrollado proporciona un método eficiente para la arilcianatión intramolecular.
La reacción ofrece una valiosa ruta a los nitriles con carbono cuaternario bencílico.
El enfoque asimétrico es prometedor para acceder a los estereocentros cuaternarios quirales.

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