Catalysis Today, Vol.133, 455-460, 2008
Transesterification of beta-ketoesters catalyzed by hybrid materials based on silica sol-gel
This work shows an alternative process for beta-ketoester transesteritication using new silica-based hybrid materials as heterogeneous catalysts. The catalysts were synthesized using silica and 3-aminopropyltriethoxysilane or 1,1,1,3,3,3-hexamethyldisilazane as functionalizating agents. beta-Ketoesters and alcohols were transesterified in refluxing toluene with reaction times between 4 h and 14 It. Different ketoesters with good performance were obtained. The influence of the catalysts and starting materials on the reaction rate was studied. In all cases, coproduct formation was not observed; the catalysts were recovered and reused without loss of catalytic activity. (c) 2007 Published by Elsevier B.V.