反应详情

4.1 G. of diethyl 6-{3-azabicyclo[3.2.2]non-3-yl}-2,4-pyrimidine-dicarbamate-3-oxide are suspended in 50 ml. of dimethylformamide and warmed to 140° C. for 30 minutes under an argon atmosphere. After cooling the solution, the dimethylformamide is distilled off under reduced pressure and the residue is filtered over silica gel. Elution with chloroform and ethanol yields ethyl 5-{3-azabicyclo[3.2.2]non-3-yl}-2-oxo-2H-[1,2,4]oxadiazolo[2,3-a]pyrimidine-7-carbamate, having a melting point of 210°-215° C. (decomposition). Analytically pure product is obtained by recrystallization from methylene chloride/ether.

1. temperatureAfter cooling the solution
2. distillationthe dimethylformamide is distilled off under reduced pressure
3. filtrationthe residue is filtered over silica gel
4. washElution with chloroform and ethanol