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Los complejos de hidruro de baja coordenada de germanio (II) y estaño (II): catalizadores eficientes para la

Terrance J Hadlington¹, Markus Hermann, Gernot Frenking

¹School of Chemistry, Monash University , P.O. Box 23, Melbourne, VIC, 3800, Australia.

Journal of the American Chemical Society

|February 15, 2014

Resumen

Los complejos de hidruro de germanio y estaño de baja valencia son catalizadores efectivos para la síntesis orgánica. Estos nuevos catalizadores promueven eficientemente la hidroboración de compuestos carbonílicos difíciles con bajas cargas de catalizador.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis es la catálisis.
Química orgánica sintética y orgánica.

Sus antecedentes:

Los hidruros metálicos de bloque p de baja valencia están poco explorados como catalizadores en la síntesis orgánica.
El desarrollo de sistemas catalíticos eficientes para la hidroboración de compuestos de carbonilo no activados sigue siendo un desafío.

Objetivo del estudio:

Investigar la actividad catalítica de complejos bien definidos de hidróxido de germanio de baja valencia (II) y de estaño (II) en síntesis orgánica.
Demostrar su eficacia en la hidroboración de diversos compuestos de carbonilo, incluidos los sustratos estéricamente obstaculizados.

Principales métodos:

Síntesis y caracterización de complejos voluminosos de hidruro de germanio (II) y estaño (II) de dos coordenadas.
Pruebas catalíticas de estos complejos en la reacción de hidroboración utilizando HBpin (pinacolato) como fuente de boro.
Evaluación de la carga del catalizador, el alcance del sustrato y la cinética de la reacción.

Principales resultados:

Los complejos de hidruro de germanio (II) y estaño (II) catalizan efectivamente la hidroboración de una variedad de compuestos de carbonilo no activados y voluminosos.
Se lograron conversiones cuantitativas con cargas de catalizador tan bajas como 0.05 mol %.
Las frecuencias de rotación excedieron las 13.300 h-1, rivalizando con los sistemas catalíticos existentes.

Conclusiones:

Los hidratos metálicos de bloque p de baja valencia bien definidos representan una nueva clase de catalizadores eficientes para la síntesis orgánica.
Estos catalizadores ofrecen una alternativa prometedora para la hidroboración de sustratos carbonílicos difíciles.
El estudio abre caminos para una mayor exploración de los complejos metálicos de bloque p en la catálisis.

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