The general procedure for the synthesis of 4-amino-6-chloropyrimidine-5-carbonitrile using 4,6-dichloropyrimidine-5-carbonitrile as starting material was as follows: 4,6-dichloropyrimidine-5-carbonitrile (4.8 g, 27.59 mmol) was suspended in 30 mL of dioxane and the mixture was cooled to 0 °C in an ice bath. A methanol solution of ammonia (7 N, 20 mL, 140 mmol) was added slowly and dropwise over a period of 20 minutes. After the dropwise addition, the reaction mixture was continued to be stirred at 0 °C for 30 min. After completion of the reaction, the solvent was removed by rotary evaporator. The crude product was redissolved in tetrahydrofuran, at which point a precipitate was generated, and the precipitate was collected by filtration and washed with additional tetrahydrofuran. The organic solvent was again removed under reduced pressure by rotary evaporator. Finally, the residue was purified using the SP1 purification system (eluent: 20%-80% hexane-ethyl acetate gradient) to afford 2.38 g (56% yield) of the target compound, 4-amino-6-chloropyrimidine-5-carbonitrile, as a white solid with 100% purity.LRMS (m/z): 155 (M + 1)+.
