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Catalizadores de hidroformilación de cobalto catiónico altamente activo

Drew M Hood¹, Ryan A Johnson¹, Alex E Carpenter²

¹Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.

Science (New York, N.Y.)

|February 1, 2020

Resumen

Los nuevos catalizadores catiónicos de cobalto ofrecen una alta actividad y selectividad para la hidroformilación de alquenos, acercándose al rendimiento del rodio. Estos catalizadores demuestran una larga vida útil y estabilidad, especialmente para los alquenos internos.

Área de la Ciencia:

Química organometálica
Catálisis
Síntesis orgánica

Sus antecedentes:

La hidroformilación utiliza tradicionalmente catalizadores de cobalto o de rodio.
Los catalizadores de rodio son muy activos pero caros.
Los catalizadores de cobalto existentes tienen limitaciones en cuanto a actividad y selectividad.

Objetivo del estudio:

Desarrollar nuevos catalizadores de cobalto con mayor actividad y selectividad.
Comparar el rendimiento de los nuevos catalizadores de cobalto con los estándares industriales existentes.
Investigar la regioselectividad de estos catalizadores para diferentes tipos de alquenos.

Principales métodos:

Síntesis de cobalto catiónico (II) complejos de hidrido-carbonilo de bisfosfina.
Evaluación de la actividad catalítica en la hidroformilación de alquenos.
Análisis de la regioselectividad lineal a ramificada (L:B) para varios alquenos.
Evaluación de la estabilidad y la vida útil del catalizador.

Principales resultados:

Los nuevos catalizadores catiónicos de cobalto presentan una actividad significativamente mayor que los catalizadores tradicionales de cobalto.
La actividad del catalizador se acerca a la de los costosos catalizadores de rodio-fosfina.
Se observa una baja regioselectividad L:B para alquenos lineales simples.
Se obtiene una alta regioselectividad L:B para alquenos internos con ramas alquilo debido a la isomerización y los efectos estéricos.
Los catalizadores muestran una larga vida útil y resistencia a la degradación.

Conclusiones:

Los catalizadores catiónicos de cobalto bisfosfina representan un avance prometedor en la hidroformilación.
Estos catalizadores ofrecen una alternativa rentable a los catalizadores de rodio.
Con estos nuevos sistemas se puede lograr una selectividad adaptada a los alquenos internos.

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