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Transformaciones paralelas del ciclohexeno mediadas por el fragmento Cp*W(NO)

Xing Jin¹, Peter Legzdins, Miriam S A Buschhaus

¹Department of Chemistry, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1.

Journal of the American Chemical Society

|May 12, 2005

Resumen

Este estudio detalla la hidrogenólisis de un complejo de tungsteno en ciclohexeno, revelando un intermediario que se somete a tres reacciones distintas. Estas reacciones incluyen la activación C-H, la hidrogenación y un nuevo acoplamiento de moléculas de ciclohexeno.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis es la catálisis.
Mecanismos de reacción Mecanismos de reacción

Sus antecedentes:

Los complejos organometálicos son cruciales en la catálisis y la ciencia de los materiales.
Comprender la reactividad de los centros metálicos de baja coordinación con hidrocarburos insaturados es clave para desarrollar nuevas metodologías sintéticas.

Objetivo del estudio:

Para investigar la vía de reacción de Cp*W(NO) ((CH2CMe3) 2 con ciclohexeno a temperatura ambiente.
Para dilucidar la formación de un complejo organometálico intermedio y sus posteriores transformaciones.
Caracterizar los productos derivados de estas vías de reacción paralelas.

Principales métodos:

Hidrogenólisis del complejo precursor en el disolvente ciclohexeno.
Aislamiento y caracterización del complejo intermedio de 16 electrones, [Cp*W ((NO)) ((eta2-ciclohexeno)) ].
Análisis de tres vías de reacción distintas del intermediario: activación C-H, hidrogenación y acoplamiento de ciclohexeno.
Análisis cristalográfico de rayos X monocristalino de los productos de las vías de hidrogenación y acoplamiento.

Principales resultados:

Formación del intermedio [Cp*W(NO) ((eta2-ciclohexeno) ] a través de la hidrogenólisis.
Observación de tres transformaciones paralelas del ciclohexeno: activación C-H, combinación con H2 y acoplamiento.
Caracterización estructural de nuevos complejos resultantes de la hidrogenación y el acoplamiento del ciclohexeno, incluido un ligando único eta1,eta3-(ciclohexilo) ciclohexenilo.

Conclusiones:

El intermedio [Cp*W(NO) ((eta2-ciclohexeno) ] es una especie versátil capaz de una reactividad diversa con el ciclohexeno.
Este estudio revela nuevas vías de reacción para los complejos organometálicos que involucran la activación C-H, la hidrogenación y el acoplamiento de ligandos.
Los datos cristalográficos proporcionan información crucial sobre las características estructurales de los complejos organometálicos resultantes.

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