Malonic Acid → 1,3-Diethylbarbituric acid

Participants

Reaction Conditions

Reaction Steps

Acetic anhydride (16 ml, 0.15 mole) was added dropwise over two hours to a solution of 1,3-diethylurea (5.3 g, 0.05 mole) and malonic acid (5.2 g, 0.05 mole) in acetic acid (40 ml) at 65° C. After the addition was complete, the temperature was raised to 90° C. and maintained there for three hours. The solvent was evaporated under reduced pressure and the residue boiled with ethanol for fifteen minutes. After some time, 1,3-diethyl-2,4,6-(1H,3H,5H)- pyrimidinetrione crystallized in cubic crystals, m.p. 52° C.

Provenance & Evidence