Epoxidation of olefins catalyzed by novel Mn(III) and Mo(IV) Salen complexes immobilized on mesoporous silica gelPart I. Synthesis and characterization of homogeneous and immobilized Mn(III) and Mo(IV) Salen complexes
作者:Tatiana Luts、Wladimir Suprun、Diana Hofmann、Olaf Klepel、Helmut Papp
DOI:10.1016/j.molcata.2006.07.035
日期:2007.1.2
New ways of the covalent immobilization of Mn(III) and Mo(IV) Salen complexes on a mesoporous silica support to produce a stable heterogeneous catalyst for epoxidation reactions are reported. Peptide and ester interactions were employed to anchor the metal Salen complex on the organo-modified silica framework. Electrospray MS, FTIR, TGA, ICP-OES and elemental analysis were used for quantitative and qualitative analyses of the immobilized Salen complexes. The results confirm the location of the metal Salen complex inside the mesopores covalently attached to the silica framework. (c) 2006 Elsevier B.V. All rights reserved.
Novel ways of Mn-Salen complex immobilization on modified silica support and their catalytic activity in cyclooctene epoxidation
作者:T. Luts、H. Papp
DOI:10.1134/s0023158407010235
日期:2007.2
The covalent immobilization of Mn(III)-Salen complexes on an amorphous mesoporous silica support is reported. Both (3-aminopropyl)trimethoxysilane (APTMS) and (3-iodopropyl)trimethoxysilane (IPTMS) were used in a post-synthesis grafting method to prepare organosilane-modified porous materials. Peptide and ester interactions were employed to anchor the Salen complex to the silica framework. The catalytic activity of the immobilized Salen catalyst was studied by epoxidation of cyclooctene. The comparison of the homogeneous and the immobilized catalyst shows that there was no significant loss of catalytic activity for epoxidation by immobilization. In the current study, the effects of reaction temperatures, solvents, and amount of catalyst on the catalytic activity were investigated. The optimal yield of cyclooctene oxide was obtained at 45 degrees C using toluene as the solvent.