反应详情

10 ml of 1 N sodium hydroxide solution were added to a suspension of 0.63 g of the product of Step B, 30 ml of water and 10 ml of ethanol and the mixture was refluxed for one hour to obtain a clear yellow solution. The ethanol was distilled under reduced pressure and the aqueous solution was acidified with concentrated hydrochloric acid. The mixture was filtered to recover 0.6 g of imidazo-[1,2-a]-quinoxaline-2-carboxylic acid in the form of a buff crystalline solid melting at 274°-275° C.

1. temperaturethe mixture was refluxed for one hour
2. customto obtain a clear yellow solution
3. distillationThe ethanol was distilled under reduced pressure
4. filtrationThe mixture was filtered
5. customto recover 0.6 g of imidazo-[1,2-a]-quinoxaline-2-carboxylic acid in the form of a buff crystalline solid melting at 274°-275° C.