RT Journal Article
ID 67bce77336841413
A1 Jadhav, Amarsinh L.
A1 Yadav, Ganapati D.
T1 GREEN SYNTHESIS OF 2,3-OXYBUTYL MALONONITRILE VIAMICHAEL REACTION OF METHYL VINYL KETONE WITH MALONONITRILE OVER TITANIA AND ZINC LOADED HYDROTALCITE CATALYSTS
JF Catalysis in Green Chemistry and Engineering
JO CGCE
YR 2019
FD 2019-04-22
VO 2
IS 1
SP 43
OP 54
K1 Zn-Al-Mg hydrotalcite
K1 Michael reaction
K1 malononitrile
K1 methyl vinyl ketone
K1 kinetics
K1 green chemistry
AB Hydrotalcites have come of age. A modification of hydrotalcite activated with zinc and titanium was used to synthesize
novel materials to catalyze Michael addition reaction of malononitrile with methyl vinyl ketone. The product of this
reaction, 2,3-oxybutylmalononitrile, has applications in pharmaceuticals, perfumery, and flavor industries, where it is
produced by non-green routes. The effect of mesoporous tubular structure in generation of mild basic sites in modified
hydrotalcite-based catalysts is discussed in this article. The reaction is atom economical from a Green Chemistry point
of view. Titanium and zinc-based hydrotalcite catalysts were synthesized by using titanium isopropoxide, zinc nitrate,
aluminum nitrate, and magnesium nitrate in basic medium by combustion synthesis using different fuels. These modified
hydrotalcites were characterized by SEM, EDXS, N2 adsorption, CO2-TPD, NH3-TPD, and XRD techniques. Zinc-modified Al-Mg hydrotalcite using glycine as the fuel was the most selective, active, and reusable catalyst. A Langmuir-Hinshelwood-Hougen-Watson (LHHW) model was used to establish the reaction mechanism and kinetics. All species were weakly adsorbed, leading to the second order power law model. Using a mole ratio of 1:2 of methyl vinyl ketone to malononitrile, with methanol as solvent and 0.01 g/cm3 catalyst loading, the reaction gave 61.9%
conversion of methyl vinyl ketone and 94.6% selectivity to 2,3-oxybutyl malononitrile in 3 h at 60°C. The apparent
activation energy was 10.12 kcal/mol. The process is green.
PB Begell House
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