resumo
We describe the preparation of an effective and reusable heterogeneous asymmetric catalyst. A novel chiral periodic mesoporous phenylene-silica containing high density of bis(oxazoline) moieties is prepared by co-condensation method with 1,4-bis(triethoxysilyl)benzene. After copper(II) coordination, the material is extremely efficient on the kinetic resolution of the 1,2-diphenylethane-1,2-diol with persistent high enantioselectivities (91 - > 99%) and yields (46-43% in maximum 50% resolution) at least for five consecutive cycles. Characterization of the material after the catalytic experiments showed that the heterogeneous catalyst was very robust keeping the integrity of the structure. (C) 2014 Elsevier Inc. All rights reserved.
palavras-chave
ENANTIOSELECTIVE CATALYSIS; KINETIC RESOLUTION; CARBON REPLICAS; ORGANOSILICA; COMPLEXES; LIGANDS; SUPPORT; CYCLOPROPANATION; IMMOBILIZATION; BISOXAZOLINES
categoria
Chemistry; Engineering
autores
Lourenco, MAO; Carneiro, L; Mayoral, A; Diaz, I; Silva, AR; Ferreira, P
nossos autores
Ana Rosa Silva
Investigador Principal
Liliana Patrícia Teixeira Carneiro
Bolseiro de investigação
Mirtha A. O. Lourenço
Investigador
Paula Celeste da Silva Ferreira
Investigador CoordenadorProjectos
agradecimentos
Authors are grateful to the Fundacao para a Ciencia e a Tecnologia (FCT), Fundo Europeu de Desenvolvimento Regional (FEDER), QREN-COMPETE, the European Union, and the Associate Laboratory CICECO for funding the Projects PTDC/QUI-QUI/64770/2006, FCOMP-01-0124-FEDER-015644 (PTDC/QUI-QUI/113678/2009), FCOMP-01-0124-FEDER-037271 (PEst-C/CTM/LA0011/2013). ARS thanks FCT, FSE and POPH for the contract under the program Ciencia 2008. ARS and PF acknowledge IF/01300/2012 and IF/00327/2013, respectively. MAOL thanks the PhD grant SFRH/BD/80883/2011. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 - ESTEEM2 (Integrated Infrastructure Initiative-I3).