Electrostatic immobilization of bis(oxazoline)-copper complexes on mesoporous crystalline materials: Cation exchange vs. incipient wetness methods

Chiral copper complexes with bis(oxazoline) and azabis(oxazoline) ligands have been immobilized by non-covalent interactions on mesoporous materials. The presence of negative charges achieved by the isomorphous substitution of silicon by aluminium is required to retain the complexes on the support....

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Detalles Bibliográficos
Autores: Feldman, Robert A., Fraile, José M.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2014
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/111780
Acceso en línea:http://hdl.handle.net/10261/111780
Access Level:acceso abierto
Palabra clave:Asymmetric catalysis
Immobilized catalysts
Bis(oxazolines)
Copper
Mesoporous materials
Descripción
Sumario:Chiral copper complexes with bis(oxazoline) and azabis(oxazoline) ligands have been immobilized by non-covalent interactions on mesoporous materials. The presence of negative charges achieved by the isomorphous substitution of silicon by aluminium is required to retain the complexes on the support. Cation-exchange was found to be not as efficient as observed with layered clays, and produce catalysts which lose their chiral ligand and give low enantioselectivity. A method employing incipient wetness produces more stable catalysts, whose activity varies to some extent according to the structure of the mesoporous material on which it is supported, and the nature of the chiral ligand. © 2014 Elsevier B.V.