Reaction #84047

Reaction equation

barbituric acid

3,5-dibromo-2-hydroxybenzaldehyde

→

product 1a

Yield 84.6%

5-(3,5-dibromo-2-hydroxybenzylidene) perhydropyrimidine-2,4,6-trione

Yield 84.6%

Solvents

acetic acid

Conditions

Workup

1. 1
   Temperaturewhile heating
2. 2
   Otherthe resulting reaction mixture
3. 3
   FiltrationThe produced crystal product was filtered
4. 4
   Washwashed with cold acetic acid
5. 5
   Washwashed with ether
6. 6
   Otherair-dried

Procedure

0.01 mol (1.28 g) of barbituric acid (5a) were dissolved in 25 ml of glacial acetic acid while heating. Then 0.011 mol (3.08 g) of 3,5-dibromo-2-hydroxybenzaldehyde (6a) were added to the obtained solution while stirring and the resulting reaction mixture was left at room temperature during 36 hours. The produced crystal product was filtered, washed with cold acetic acid, then washed with ether and air-dried. Thereby 3.3 g of product 1a were obtained in the form of yellow needle crystals with melting temperature of 255-260° C. (with decomposition). Output amounted to 77% of the theoretical value.

Source