Novel solid base catalysts for Michael additions - Synthesis, Characterization and Application
نویسنده
چکیده
In contrast to solid acid catalysts, much fewer efforts have been made to study solid base catalysts. In this thesis, preparation, characterization and application of oxides and modified oxide as solid base catalysts were studied. The catalysts include MgO prepared by different methods, potassium-modified ZrO2, calcined Mg-Al hydrotalcites, and a novel catalyst system Mg(O,F), which was prepared by sol-gel method for the first time. The catalysts were studied by N2 adsorption/desorption measurement, XRD, FTIR, XPS, TGDTA-DTG and NMR. Acid-base properties of the catalysts were investigated by TPD, FTIR spectroscopy and microcalorimetry to correlate with the catalytic behavior. Calcined Mg-Al hydrotalcite and Mg(O,F) are found to be highly active and selective catalysts for liquid-phase Michael additions of CH-acid compounds with methyl vinyl ketone.
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