1007-99-4

1194-21-4

1007-99-4

General procedure for the synthesis of 2-amino-4-chloro-5-nitro-6-hydroxypyrimidines from 2-amino-6-chloro-4-hydroxypyrimidines: 2-amino-6-chloropyrimidin-4(3H)-one (10 g, 68.73 mmol) was dissolved in 98% sulfuric acid (46 mL) at 40 °C, keeping stirring. Subsequently, 65% nitric acid (9 g) was slowly added dropwise to the above solution. The reaction mixture was continued to be stirred at room temperature for 1 hour. Upon completion of the reaction, the solution was carefully poured into 100 g of ice to quench the reaction. The precipitate was collected by filtration and the resulting filter cake was dried in a reduced pressure oven to afford 12 g (87% yield) of the target product 2-amino-6-chloro-5-nitropyrimidin-4(3H)-one as a yellow solid. The structure of the product was confirmed by 1H NMR (300 MHz, DMSO-d6): δ 7.13 (1H, s), 8.59 (1H, s), 12.16 (1H, s).