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Activación deshidroalquiladora de los catalizadores de rutenio CNN y PNN Pincer para la hidrogenación de ésteres

Tianyi He¹, John C Buttner¹, Eamon F Reynolds¹

¹Department of Chemistry , Colgate University , 13 Oak Drive , Hamilton , New York 13346 , United States.

Journal of the American Chemical Society

|October 8, 2019

Resumen

Los complejos de rutenio-pinza liberan alcanos durante la hidrogenación del éster, formando catalizadores de imina activos. Estos catalizadores hidrogenan eficientemente los ésteres a temperatura ambiente, revelando nuevos conocimientos sobre los intermedios catalíticos.

Área de la Ciencia:

Química organometálica
Catálisis
Síntesis orgánica

Sus antecedentes:

Los complejos de rutenio-pinza son conocidos como precatalizadores para la hidrogenación de ésteres.
La deshidroalquilación de estos complejos puede producir especies de rutenio (0).

Objetivo del estudio:

Para investigar los intermediarios catalíticos en la hidrogenación del éster catalizado por pinzas de rutenio.
Desarrollar catalizadores altamente activos para la hidrogenación de ésteres.

Principales métodos:

Síntesis y caracterización de los complejos rutenio-pinzón.
Experimentos de hidrogenación por éster catalítico.
Estudios sobre el curso del tiempo e investigaciones mecanicistas.

Principales resultados:

Los complejos de rutenio-pinza se someten a deshidroalquilación para formar complejos de rutenio ((0) -imina.
La liberación de alcanos es concomitante con el inicio de la catálisis de hidrogenación de ésteres.
Un nuevo complejo de rutenio ((0) -imina exhibe una alta actividad para la hidrogenación de ésteres a temperatura ambiente (hasta 15.500 volúmenes de negocio).
El complejo de rutenio ((0)) -imina reacciona de manera reversible con H2 para formar un complejo de rutenio ((II) -dihidruro.

Conclusiones:

Las especies catalíticas activas en la hidrogenación de ésteres pueden incluir intermedios de rutenio ((0) -imina.
Los complejos de pinzas de rutenio ofrecen una plataforma versátil para desarrollar catalizadores de hidrogenación eficientes.
Estos hallazgos tienen implicaciones significativas para la comprensión de los mecanismos catalíticos en las reacciones de hidrogenación.

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