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Isomerización heterogénea para la hidrogenación estereoselectiva de alquinos a transalquenos mediados por átomos de

Weijie Zhang¹, Ruixuan Qin¹, Gang Fu¹

¹State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials and National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

Journal of the American Chemical Society

|September 17, 2021

Resumen

Este estudio introduce un nuevo mecanismo para la producción selectiva de alquenos a través de la hidrogenación alquina, logrando altos rendimientos de transolefinas. Este nuevo enfoque utiliza átomos de hidrógeno frustrados en catalizadores defectuosos para controlar la estereoselectividad y prevenir la sobrehidrogenación.

Área de la Ciencia:

Catálisis
Química orgánica
Ciencias de los materiales

Sus antecedentes:

La hidrogenación alquina generalmente produce cis-olefinas debido al mecanismo de Horiuti-Polanyi en las superficies metálicas.
El logro de la producción estereoselectiva de transolefinas sigue siendo un desafío importante en la síntesis química.

Objetivo del estudio:

Desarrollar un nuevo sistema catalítico para la síntesis estereoselectiva de transolefinas a partir de la hidrogenación de alquinos.
Para aclarar un nuevo mecanismo de isomerización que cambia la selectividad de cis- a trans-olefinas.

Principales métodos:

Investigaciones teóricas y experimentales combinadas.
Utilizó un catalizador Rh2S3 (110) defectuoso y nanohojas Rh-S/Pd bifuncionales.
Investigó un nuevo mecanismo de isomerización mediado por átomos de hidrógeno frustrados.

Principales resultados:

Demostró un nuevo mecanismo para la isomerización cis-trans de las olefinas mediada por átomos de hidrógeno frustrados.
El Rh2S3 (110) defectuoso mostró un alto rendimiento para la producción de transolefinas, inhibiendo la sobrehidrogenación.
Las nanohojas bifuncionales Rh-S/Pd lograron una excelente actividad y estereoselectividad en la hidrogenación de un solo alquino a transolefinas.

Conclusiones:

Una nueva estrategia catalítica permite la síntesis estereoselectiva de las transolefinas a través de la hidrogenación alquina.
El mecanismo de isomerización mediado por átomos de hidrógeno frustrado ofrece una vía para controlar la configuración de olefinas.
Desarrolló catalizadores bifuncionales que superan los sistemas homogéneos y heterogéneos existentes para la producción de transolefinas.

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