54368-62-6

Ethyl 2,6-dichloro-5-nitropyrimidine-4-carboxylate (1 g, 3.76 mmol, 1.00 eq.) was used as starting material to form a suspension with stannous chloride dihydrate (3.38 g, 14.98 mmol, 1.00 eq.) in ethyl acetate (30 mL). The mixture was transferred to a 50 mL sealed tube and the reaction was stirred at 70 °C for 5 hours. Upon completion of the reaction, the resulting solution was diluted with 50 mL of water and the pH was adjusted with sodium carbonate to 9. Subsequently, extraction was carried out with ethyl acetate (3 x 100 mL), and the organic phases were combined, washed sequentially with water and brine, and dried over anhydrous sodium sulfate. The solvent was removed by concentration under reduced pressure and the resulting residue was purified by silica gel column chromatography with the eluent ethyl acetate/petroleum ether (1:5) to afford the target product ethyl 5-amino-2,6-dichloro-4-pyrimidinecarboxylate (572 mg, 64% yield) as a light yellow solid.LC-MS (ES, m/z): 236 [M + H]+.

[1] Patent: US2015/57260, 2015, A1. Location in patent: Paragraph 0743; 0744; 1003; 1004
[2] Patent: WO2015/25026, 2015, A1. Location in patent: Page/Page column 174