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 was catalyzed by different Bronsted and Lewis acids.
Methods:
The catalytic
effect of different metal chloride such as sodium, potassium, magnesium, stannous, ferric, manganese, cupric, nickel, cobalt, and
zinc chlorides in absence and presence of acetic acid were studied. Results: The zinc, ferric, cupric, and cobalt chlorides were
found to be more effective catalysts for Biginelli reaction at room temperature. The yield of reaction was increases with
temperature for all catalytic system. Acetophenone, cyclohexanone, acetyl acetone, and different β-ketoesters forming
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
Results:
The zinc, ferric, cupric, and cobalt chlorides were
found to be more effective catalysts for Biginelli reaction at room temperature. The yield of reaction was increases with
temperature for all catalytic system. Acetophenone, cyclohexanone, acetyl acetone, and different β-ketoesters forming
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 effective greener catalyst system for Biginelli reaction.