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Strong Organic Bases as Building Blocks of Mesoporous Hybrid Catalysts for C-C Forming Bond Reactions
No full text[EN] 1,8-Bis(tetramethylguanidino)naphthalene (TMGN), a neutral organic base that combines the properties of guanidine and the properties of proton sponges, was used as a building block to produce organicinorganic silica-based mesoporous hybrids with strong basic properties. The TMGN-based mesoporous hybrids (TMGN/SiO2) were prepared by a solgel route working at a neutral pH and low temperatures, which avoided the use of SDAs. TMGN has been modified in order to have two terminal reactive silyl groups able to perform co-condensation with a conventional organosilane (TMOS) used as a silicon source. This synthesis has allowed us to directly introduce the unmodified, functionalized TMGN as part of the walls of the mesoporous silica by a one-pot synthesis. TMGN/SiO2 hybrid materials present excellent catalytic properties for CC bond forming reactions: Knoevenagel, Henry (nitroaldol), and ClaisenSchmidt condensations. The activity of the hybrid materials is higher than that of the counterpart homogeneous catalyst.The authors thank the Spanish Government by Consolider Ingenio 2010 MULTICAT (number CSD2009-00050) and MAT2011 (number 29020-C02-01) projects. E. G. is grateful for the financial support from the Marie Curie Fellowship (grant number FP7-PEO-PLE-2009-IEF).Gianotti, E.; Díaz Morales, UM.; Velty, A.; Corma Canós, A. (2012). Strong organic bases as building blocks of mesoporous hybrid catalysts for C-C forming bond reactions. European Journal of Inorganic Chemistry. 32:5175-5185. https://doi.org/10.1002/ejic.201200716S5175518532Wight, A. P., & Davis, M. E. (2002). Design and Preparation of Organic−Inorganic Hybrid Catalysts. Chemical Reviews, 102(10), 3589-3614. doi:10.1021/cr010334mBigi, F., Carloni, S., Maggi, R., Mazzacani, A., & Sartori, G. (2000). 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Going Beyond Counting First Authors in Author Co-citation Analysis
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