Background: Biginelli reaction is the most well-known and widely studied, multicomponent
reaction used for the direct synthesis of many biologically active 3,4-dihydropyrimidin-
2(1H)-ones and their derivatives by reacting a β-keto ester/1,3-dicarbonyl compound, an aldehyde,
and urea. It is catalyzed by different Bronsted and Lewis acids.
Methods: The catalytic effect of different metal chlorides, such as sodium, potassium, magnesium,
stannous, ferric, manganese, cupric, nickel, cobalt, and zinc, in absence and presence of acetic acid
Results: The zinc, ferric, cupric, and cobalt chlorides were found to be more effective catalysts for
Biginelli reaction at room temperature. The yield of the reaction increased with temperature for all
catalytic systems. Acetophenone, cyclohexanone, acetyl acetone, and different β-ketoesters formed
tetrahedropyrimidine in moderate to good yield, by using zinc chloride catalyst at room
temperature in acetic acid. The efficiency of the catalyst was studied by treating different
substituted aldehydes with 1,3-dicarbonyl compounds and urea at room temperature.
Conclusion: The zinc chloride in acetic acid found to be an effective greener catalyst system for