Hydrochloric Acid → 1-Cyclohexyl-4-oxo-4,5-dihydroimidazo[1,5-a]quinoxaline-7-carboxylic acid

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Reaction Steps

Ethyl 1-cyclohexyl-4-oxo-4,5-dihydroimidazo[1,5-a]-quinoxaline-7-carboxyate as synthesized in the above Example 57, 3.33 g, ethanol 14 mL and 1N aqueous sodium hydroxide solution 29.4 mL were mixed, and heated under reflux for an hour in nitrogen atmosphere. The reaction liquid was allowed to cool off, and its pH was adjusted to 7 by addition of diluted hydrochloric acid. The precipitated crystals were recovered by filtration, washed with water and dried by heating under reduced pressure to provide 2.96 g of the title compound.

Provenance & Evidence