反应详情

1 G. of diethyl 6-dimethylamino-2,4-pyrimidine-dicarbamate-3-oxide is heated to 140° C. for 30 minutes in 10 ml. of N,N-dimethylformamide under an argon atmosphere. The solution is cooled and the solvent is evaporated under reduced pressure. The crystalline residue is recrystallized from methylene chloride/ethanol, there being obtained pure ethyl 5-dimethylamino-2-oxo-2H-[1,2,4]oxadiazolo[2,3-a]pyrimidine-7-carbamate, having a melting point of 230°-240° C.

1. temperatureThe solution is cooled
2. customthe solvent is evaporated under reduced pressure
3. customThe crystalline residue is recrystallized from methylene chloride/ethanol, there