77287-34-4

149506-35-4

706811-25-8

To a stirred solution of 100 g of dimethyl 2-(4-bromophenyl)malonate (0.348 mol) dissolved in 400 cm3 methanol at 20-25 °C, 30 g of formamide (0.66 mol) and 30 g of sodium methanolate (0.555 mol) were added sequentially. The reaction mixture was heated to 70 °C and maintained at this temperature until the reaction was complete (monitored by HPLC). After completion of the reaction, methanol was removed by distillation under reduced pressure at 70°C to give a syrupy substance. The syrup was cooled to 25-30 °C and diluted with 2 dm3 water. The pH of the solution was adjusted to 2-2.5 with concentrated hydrochloric acid and this pH was maintained for 45 min. The precipitated solid was collected by filtration and washed with water until the filtrate reached pH 7-7.5. The product was blotted dry and dried under reduced pressure at 100°C to give the crude product 5-(4-bromophenyl)-6-hydroxypyrimidin-4(1H)-one. The crude product was dissolved in 500 cm3 methanol and heated to 60-65°C and kept for 1 hour. The reaction mixture was then cooled to 25-30°C and left to stand for 30 minutes. The resulting solid was filtered, washed with methanol and dried under reduced pressure at 50-55°C to give the pure product 5-(4-bromophenyl)-6-hydroxypyrimidin-4(1H)-one. Yield: 70 g (75.25%); HPLC purity: 99.5%; melting point: 176-180 °C. The spectral data of the obtained compounds were in agreement with literature reports [8].