Publication Type Journal Article
Title Alkene epoxidation by manganese(III) complexes immobilized onto nanostructured carbon CMK-3
Authors H. Gaspar Marta A. Andrade Clara Pereira S. L. H. Rebelo Joao P. Araujo J. M. P. Silva Ana P. Carvalho C Freire
Groups
Journal CATALYSIS TODAY
Year 2013
Month March
Volume 203
Number
Pages 103-110
Abstract New heterogeneous catalysts were prepared through immobilization of Mn(III) complexes onto CMK-3 with different surface treatments. The [Mn(TF5PP)Cl] and [Mn(5-HOsalhd)Cl] complexes were anchored by a microwave-assisted protocol (CAT I and CAT III, respectively) and the Jacobsen catalyst was immobilized using conventional synthesis conditions (CAT II). XPS and FTIR revealed that the CMK-3 target functionalities for immobilization were the surface oxygen groups. XRD showed that the support treatments led to a decrease of its 2D-hexagonal order, but the complex grafting did not induce changes on the microstructure. CAT I was active in the epoxidation of cis-cyclooctene by H2O2, with substrate conversions and epoxide selectivities in the ranges of 38-30\% and 100-97\%, respectively, in three cycles with almost no complex leaching. CAT II was active in the epoxidation of 6-cyano-2,2-dimethylchromene using m-CPBA/NMO system with a substrate conversion similar to that of the free complex and higher ee \%, but with some Mn leaching in the catalytic runs. CAT III was active in the epoxidation of indene, by H2O2, in ethanol with substrate conversions, epoxide selectivities and ee \% values in the ranges of 45-37\%, 83-86\% and 10-12\%, respectively. A correlation between the structural properties of the supports and the reaction times could be proposed. These results highlight the potentiality of CMK-3 to act as support for metal complexes with catalytic properties in oxidation reactions. (C) 2012 Elsevier B. V. All rights reserved.
DOI http://dx.doi.org/10.1016/j.cattod.2012.04.018
ISBN
Publisher
Book Title
ISSN 0920-5861
EISSN 1873-4308
Conference Name
Bibtex ID ISI:000314825300016
Observations
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