反应详情

A mixture of 5-methylisocytosine (3 g, 24.0 mmol) and POCl3 (20 mL) was refluxed for 45 minutes. Excess of POCl3 was removed under reduced pressure and the residue was poured over ice. The resulting mixture was made basic with ammonia at 10° C. The precipitate was filtrated and crystallized from ethanol to give 4-chloro-2-amino-5-methylpyrimidine (1 g 29.0% yield). 1H NMR (400 MHz, DMSO): δ 8.11 (s, 1H), 6.81 (br s, 2 H), 2.04 (s, 3H).

1. temperaturewas refluxed for 45 minutes
2. customExcess of POCl3 was removed under reduced pressure
3. additionthe residue was poured over ice
4. customwas made basic with ammonia at 10° C
5. filtrationThe precipitate was filtrated
6. customcrystallized from ethanol