5-propan-2-yl-1,3-diazinane-2,4,6-trione

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Sodium metal (1.28 kg, 55.65 mol) was dissolved in ethanol (25 L) under nitrogen atmosphere at 0° C. (bath temperature). Diethyl malonate (7.45 kg, 46.51 mol) was added to the solution and the mixture was heated to 80° C. 2-Bromopropane (8.00 kg, 65 mol) was added dropwise to the solution for 1 hour, and the solution was refluxed for 10 hours. The solution was cooled to room temperature. Sodium metal (1.22 kg, 53.04 mol) was dissolved into the solution under nitrogen atmosphere at 0° C. Urea (2.78 kg, 46.28 mol) in methanol (15 L) was added to the solution over 2 hours and the reaction mixture was refluxed for 20 hours. The reaction mixture was diluted with water (35 L) and conc. HCl (5 L), and cooled to room temperature. The precipitate was collected by filtration, washed with water (20 L), ether (15 L), n-hexane (20 L) and dried in vacuum at 40° C. for 10 hours to give 5-isopropylbarbituric acid as a white solid (3.42 kg, 20.10 mol, 43% yield). the solution was refluxed for 10 hours The solution was cooled to room temperature the reaction mixture was refluxed for 20 hours cooled to room temperature The precipitate was collected by filtration washed with water (20 L), ether (15 L), n-hexane (20 L) dried in vacuum at 40° C. for 10 hours

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 456 g (2.25 mol) of diethyl isopropylmalonate, 650 ml of a 30% methanolic sodium methoxide solution and 910 ml of methanol are charged to a 2 liter reactor equipped with an anchor stirrer. The mixture is brought to reflux for thirty minutes before adding 135 g (2.25 mol) of urea in the solid form while maintaining the reflux. The reaction mixture at the end of the reaction is a thick white suspension which is brought to dryness by evaporation of the methanol under vacuum. The residue is taken up in 1370 ml of water and then filtered after cooling to 20° C. The filtrate is treated by addition of the amount of hydrochloric acid needed to bring the pH to 2-3, and the precipitate obtained is filtered off under cold conditions and washed with ice-cold water in order to obtain 267 g of 5-(1-methylethyl)pyrimidine-2,4,6(1H,3H,5H)-trione. equipped with an anchor stirrer to reflux for thirty minutes while maintaining the reflux is brought to dryness by evaporation of the methanol under vacuum filtered The filtrate is treated by addition of the amount of hydrochloric acid the precipitate obtained is filtered off under cold conditions washed with ice-cold water in order