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Un catalizador de NHC-diboreno para la hidroboración

Jun Fan¹, Jian-Qiang Mah¹, Ming-Chung Yang²

¹Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371.

Journal of the American Chemical Society

|January 15, 2021

Resumen

Un nuevo catalizador de N-fosfinoamidinato NHC-diboreno cataliza efectivamente la hidroboración del dióxido de carbono (CO2) y la N-formalización de aminas. Este catalizador demuestra una alta eficiencia y selectividad en la activación de CO2 y compuestos de carbonilo.

Área de la Ciencia:

Química organometálica
Catálisis
Química del boro

Sus antecedentes:

El desarrollo de catalizadores eficientes para la utilización del CO2 es crucial para la química sostenible.
Los ligandos de carbenos N-heterocíclicos (NHC) son ampliamente utilizados en la catálisis organometálica.
Los compuestos de diboreno con enlaces dobles B = B ofrecen vías de reactividad únicas.

Objetivo del estudio:

Sintetizar y caracterizar un nuevo complejo N-fosfinoamidinato NHC-diboreno.
Investigar la actividad catalítica del complejo sintetizado en reacciones de hidroboración.
Explorar el potencial del catalizador en la activación y la funcionalidad del CO2.

Principales métodos:

Síntesis del catalizador N-fosfinoamidinato de NHC-diboreno mediante reacciones en varias etapas en las que intervienen organolitio y haluros de boro.
Caracterización del catalizador mediante técnicas espectroscópicas.
Pruebas catalíticas en la hidroboración de CO2 con pinacolborano y en la N-formalización de aminas.

Principales resultados:

Se sintetizó con éxito el nuevo compuesto N-fosfinoamidinato NHC-diboreno (2).
El catalizador 2 catalizó eficientemente la hidroboración de CO2 con pinacolborano, obteniendo metoxiborano y óxido de bis (borilo) con una alta conversión (>99%).
El catalizador 2 también catalizó con eficacia la N-formación de aminas primarias y secundarias utilizando CO2 y pinacolborano, logrando altos rendimientos (promedio. 91,6%). En el Reino Unido

Conclusiones:

El catalizador N-fosfinoamidinato de NHC-diboreno tiene un potencial significativo para la valorización del CO2.
El catalizador demuestra una amplia aplicabilidad en reacciones de hidroboración y N-formilación.
El enlace doble B = B en el diboreno es clave para la activación del sustrato y la rotación catalítica.

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