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Updated: Mar 1, 2026

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Acoplamiento catalítico deshidrogenativo C-C por un complejo de iridio ligado por pinza

Miles Wilklow-Marnell¹, Bo Li², Tian Zhou²

¹Department of Chemistry, University of Rochester , Rochester, New York 14627, United States.

Journal of the American Chemical Society

|June 9, 2017

Resumen

Los catalizadores de iridio y pinza facilitan el acoplamiento deshidrogenativo de los arenos vinílicos para formar diarilbutadienos. Esta reacción puede proceder por desproporcionamiento o con aceptores de hidrógeno, dando hasta un 90% de producto.

Área de la Ciencia:

Química organometálica
Catálisis
Síntesis orgánica

Sus antecedentes:

Las arenas de vinilo son bloques de construcción versátiles en la síntesis orgánica.
Los métodos catalíticos eficientes para la funcionalización de C-H son muy buscados.

Objetivo del estudio:

Investigar la actividad catalítica de los complejos pinza-iridio en el acoplamiento deshidrogenativo de las arenas vinilo.
Para aclarar el mecanismo de reacción y explorar el alcance del sustrato.

Principales métodos:

Catálisis con fragmentos de iridio de pinza (iPrPCP) Ir.
Cálculos de la Teoría Funcional de la Densidad (DFT).
Síntesis y caracterización de los productos intermedios del metalloindeno.
Reacciones con estirenos sustituidos.

Principales resultados:

Formación predominante de (E,E) -1,4-diarilo-1,3-butadienos mediante el acoplamiento deshidrogenativo.
El rendimiento de hasta el 90% se consigue mediante desproporcionamiento o con aceptores de hidrógeno de sacrificio.
El mecanismo implica la adición de doble C-H para formar un intermediario de iridio (III) metaloindeno.
Se ha demostrado el acoplamiento de enlaces C(sp2)-H y C(sp3)-H utilizando 2,4,6-trimetilestireno.

Conclusiones:

Los complejos de pinza e iridio son catalizadores eficaces para el acoplamiento deshidrogenativo del vinil areno.
La reacción se lleva a cabo a través de un intermediario de metalloindeno.
El sistema catalítico es versátil y puede acoplar varios enlaces C-H.

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