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Inserción de areno con hidritos de molibdeno apoyados en pinzas: determinación de la selectividad del sitio, tasas

Gabriele Hierlmeier¹, Paolo Tosatti², Kurt Puentener²

¹Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.

Journal of the American Chemical Society

|September 13, 2023

Resumen

Los investigadores desarrollaron nuevos complejos de molibdeno para la hidrogenación selectiva del areno. Estos complejos permiten la inserción controlada en arenas, dando lugar a valiosos hidratos de ciclohexadienilo y productos potencialmente enriquecidos con enantio.

Área de la Ciencia:

Química organometálica
Catálisis
Síntesis orgánica

Sus antecedentes:

Los complejos de molibdeno son catalizadores versátiles en las transformaciones orgánicas.
La hidrogenación del areno es una reacción clave en la química sintética.
El control de la selectividad del emplazamiento en la funcionalización continua siendo un reto.

Objetivo del estudio:

Para sintetizar nuevos complejos de molibdeno apoyados en fosfino (oxazolina) piridina (0).
Investigar la reactividad de estos complejos en la hidrogenación del areno.
Explorar los factores que influyen en la selectividad del sitio y las tasas de reacción.

Principales métodos:

Síntesis de complejos de molibdeno ((0) cicloocta-1,5-dieno.
Reacción con dihidrógeno y varios arenes sustituidos.
Análisis de los productos de inserción y determinación de las tasas relativas mediante experimentos de competencia.

Principales resultados:

Los hidratos de ciclohexadienilo de molibdeno se formaron a través de la inserción de areno.
La selectividad del sitio aumentó con el tamaño del sustituyente para las arenas mono y disubstituidas.
Las arenas ricas en electrones mostraron tasas de inserción más rápidas.
Los grupos de retirada de electrones alteraron la selectividad y favorecieron la eliminación reductiva de H2.
Se sintetizó ciclohexa-1,3-dieno enriquecido con enantio.

Conclusiones:

El diseño del ligando influye en la hidrogenación catalítica del areno.
Se desarrolló una nueva estrategia para la reducción selectiva de arsenales.
Se obtuvieron conocimientos sobre la funcionalización del areno catalizado por molibdeno.

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