反应详情

To a solution of 0.23 g. (0.01 g. atoms) of sodium in 100 ml. of ethanol was added 2.76 g. (0.01 mole) of 1-ethyl-1,2-dihydro-4-hydroxy-7-methyl-2-oxo-1,8-naphthyridine-3-carboxylic acid ethyl ester prepared by the method of Example 1. The mixture was stirred at room temperature for 2 hours. The mixture was filtered and the filter cake was dissolved in boiling ethanol. After cooling, the solution was diluted with diethyl ether to the cloudy point. Further cooling produced a precipitate which was collected to give 1.1 g. of the title compound, m.p. >300° C.

1. filtrationThe mixture was filtered
2. dissolutionthe filter cake was dissolved
3. temperatureAfter cooling
4. additionthe solution was diluted with diethyl ether to the cloudy point
5. temperatureFurther cooling
6. customproduced a precipitate which
7. customwas collected
8. customto give 1.1 g