Structural properties of alumina- and silica-supported Iridium catalysts and their behavior in the enantioselective hydrogenation of ethyl pyruvate

Iridium catalysts were prepared using alumina or silica as supports and two preparation methods, incipient wetness impregnation and flame spray pyrolysis. These catalysts were characterized, after reduction in hydrogen, by transmission electron microscopy, infrared spectroscopy of adsorbed CO and mi...

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Detalles Bibliográficos
Autores: Dongil, Ana Belén, Bachiller-Baeza, B., Rodríguez-Ramos, Inmaculada, Guerrero-Ruiz, Antonio, Mondelli, C., Baiker. A.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2013
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/182432
Acceso en línea:http://hdl.handle.net/10261/182432
Access Level:acceso abierto
Palabra clave:Iridium catalysts
Microcalorimetry
Ethyl pyruvate
Asymmetric hydrogenation
Descripción
Sumario:Iridium catalysts were prepared using alumina or silica as supports and two preparation methods, incipient wetness impregnation and flame spray pyrolysis. These catalysts were characterized, after reduction in hydrogen, by transmission electron microscopy, infrared spectroscopy of adsorbed CO and microcalorimetry of CO chemisorption. Aliquots of these catalysts were tested in the ethyl pyruvate hydrogenation using cinchonidine as a chiral modifier. Different enantioselectivities to (R)-ethyl lactate were obtained depending on the support material and the preparation method. Based on the structural characterization it is proposed that the different enantioselectivities are mainly due to different surface structure of the iridium nanoparticles caused by the support interaction.