反应详情

A suspension of 10 g of 3-ethoxycarbonyl-1-ethyl-1,4-dihydro-7-methoxy-4-oxo-1,8-naphthyridine-6-diazonium tetrafluoroborate in 300 ml of xylene was heated under reflux for 30 minutes. After evaporation of the xylene, the residue was taken up in chloroform. The chloroform solution was washed with water and the solvent was distilled off. The crude product was chromatographed on silica gel with chloroform as an eluent to give 3.6 g of ethyl 1-ethyl-6-fluoro-1,4-dihydro-7-methoxy-4-oxo-1,8-naphthyridine-3-carboxylate, m.p. 181°-182° C.

1. temperaturewas heated
2. temperatureunder reflux for 30 minutes
3. customAfter evaporation of the xylene
4. washThe chloroform solution was washed with water
5. distillationthe solvent was distilled off
6. customThe crude product was chromatographed on silica gel with chloroform as an eluent