反应详情

Bromine (0.85 mL, 0.0166 mole) was added dropwise over 20 minutes to a stirred suspension of 2-amino-4,6-dichloropyrimidine (CAS#56-05-3, 1.70 g, 0.01037 mole) and sodium carbonate (1.00 g, 0.01244 mole) in 1:1 methanol/water (30 mL) at ambient temperature. Ten minutes after the addition was complete, more sodium carbonate (0.78 g, 0.0093 mole) was added to the reaction mixture. The reaction mixture was stirred at ambient temperature for 42 hours, then it was diluted with aqueous sodium bicarbonate to provide 5-bromo-4,6-dichloropyrimidin-2-amine as a precipitate that was collected by filtration and rinsed with water. The vacuum-dried solid weighed 2.11 g (83.7% yield). 1H NMR (300 MHz, d6-DMSO) δ ppm 7.67 (s, 1H), 7.70 (s, 1H). MS (DCl—NH3) m/z=241 (M+H)+, m/z=258 (M+NH4)+.

1. additionTen minutes after the addition