STUDY OF HETEROGENEOUS CuHY ZEOLITE CATALYSTS USING IN BIGINELLI REACTION

Abstract

In this work synthetic Y zeolite catalysts were modified by copper and sulfur loading and used for the
Biginelli reaction to synthesize 3,4-dihydropyrimidine-2(1H)-on (DHPM). The Cu(II)-Y zeolites
(CuHY) with different content of copper (CuHY2.5%; CuHY5.7%; CuHY8.6%) obtained via liquid
phase ion exchange method while the sulfated Y zeolites (HYS) were prepared by impregnating zeolite
Y in acid H2SO4. The characterization of the synthesized catalysts was carried out using the various
physico-chemical methods such as the X-ray powder diffractometer (XRD) and X-ray fluorescence
(XRF). All the characterization techniques used suggest and confirm the existence of the copper, sulfer
on the surface of Y-zeolite. The affecting conditions to the Biginelli reaction in synthesis of 3,4-
dihydropyrimidine-2(1H)-on (DHPM) compounds using catalysts have been studied. The suitable
conditions for the reaction were found as catalyst CuHY8,6%; toluene as a solvent; reaction time of 72
hours with maximum efficiency. The yield of the reaction increased proportionally to the content of
Cu2+ in a zeolite (CuHY8,6%> CuHY5,7%> CuHY2,5%> HYS) and higher than that of the reaction using
zeolite sulfate Y. Eight DHPM derivatives were synthesized with 35-51% yield, of which two new
compounds were found. Activity of reusable catalyst was the same fresh catalyst. The structures of the
reaction products were confirmed by IR, NMR and MS methods