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Activación del hidrógeno y la catálisis de hidrogenación por un catión de borenio

Jeffrey M Farrell¹, Jillian A Hatnean, Douglas W Stephan

¹Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6.

Journal of the American Chemical Society

|August 31, 2012

Resumen

Una nueva sal de borenio activa fácilmente el gas hidrógeno y cataliza la hidrogenación libre de metales de iminas y enaminas a temperatura ambiente, ofreciendo una nueva vía en la química sintética.

Área de la Ciencia:

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

Sus antecedentes:

Las sales de borenio son compuestos de boro ácido de Lewis.
La activación del hidrógeno es crucial para muchas transformaciones químicas.
La catálisis libre de metales ofrece alternativas sostenibles en la síntesis orgánica.

Objetivo del estudio:

Para investigar la reactividad de una sal de borenio preparada fácilmente.
Explorar su potencial en la activación y catálisis del hidrógeno.
Desarrollar un método de hidrogenación sin metales para las iminas y las enaminas.

Principales métodos:

Síntesis y caracterización de la sal de borenio [{IiPr{2}) }{BC{8}H{1}) ][B{C{6}F{5}) {4}] (2).
Estudios de activación heterolítica de H2 en presencia de tBu3P.
Hidrogenación catalítica de iminas y enaminas utilizando el compuesto 2 a temperatura ambiente.

Principales resultados:

La sal de borenio (2) activó con éxito el H2 heterolíticamente con tBu3P.
El Compuesto 2 demostró actividad catalítica para la hidrogenación libre de metales de iminas y enaminas.
Las reacciones procedieron eficientemente a temperatura ambiente, lo que indica condiciones de reacción suaves.

Conclusiones:

La sal de borenio (2) es un reactivo eficaz para la activación heterolítica de H2O.
El compuesto 2 sirve como un catalizador competente para la hidrogenación libre de metales de enlaces C=N y C=C.
Este trabajo presenta un valioso sistema catalítico sin metales para la síntesis orgánica.

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