alkali and alkaline earth metals hydrogen sulfate catalyzed the one-pot three component condensation reactions of aldehydes, 1,3-dicarbonyl compounds and urea or thiourea under solvent-free conditions leading to 3,4-dihydropyrimidin-2(1h)-ones in high yields at 80 °c. our results showed that biginelli reaction not only is ph dependent, but the cation of catalyst plays an important role.

microwave-assisted three component cyclocondensation reactions of aldehydes, amides and dienophiles in the presence of acetic anhydride and para-toluenesulfonic acid as a catalyst to afford the highly substituted cyclohexene derivatives, in relatively good yields after several minutes are reported.

a highly efficient procedure for the preparation of n,n'-alkylidenebisamides in the presence of bf3.sio2 as a catalyst is described. n,n'-alkylidenebisamides have been prepared via one-pot three-component condensation reaction of various aldehydes and amides. all of the reactions proceeded in high yields and in moderately short reaction times.

in this work, the efficiency, generality and applicability of new bronsted acidic ionic liquid (bail) 1-methyl-3-(2-(sulfooxy)ethyl)-1h-imidazol-3-ium chloride {[msei]cl} as heterogeneous and green catalyst for organic transformations are studied. herein, the following one-pot multi-component reactions in the presence of [msei]cl are investigated: (i) the synthesis of quinoxaline derivatives fr...

In this study, multi component Hantzsch reaction was carried out between various  Aromatic Aldehyde with Dimedone,Ethyl acetateand ammonium acetate to produce polyhydroquinolinederivatives under solvent-free conditions at 110oC by a (Zinc oxide  nanocatalyst) as effective Lewis acid. The remarkable advantages offered by this method compared with other methods are a green catalyst, si...