Potassium Hydroxide → HCID 178524847, compound

Participants

Reaction Steps

Potassium hydroxide (1.25 g, 22.2 mmol) was added to a suspension of 6-chloro-2-(ethoxycarbonyl)-3-hydroxyquinoxaline (0.56 g, 2.22 mmol) in 2-propanol (5 mL) and water (7.5 mL) and the resulting solution were heated at reflux for 12 h. The cooled mixture was acidified to pH 2 and the solvents were removed under reduced pressure, after which the residue was taken up in water (50 mL) and extracted with ethyl acetate (2×40 mL). The organic extracts were combined and the solvents were removed under reduced pressure, producing a residue that was purified by flash column chromatography on silica gel, eluting with methanol/methylene chloride (1:9), to provide 6-chloro-3-hydroxyquinoxaline-2-carboxylic acid as a light yellow solid: 1H NMR (400 MHz, CD3OD) δ 7.91 (d, 1H), 7.45 (d, 1H), 7.37 (dd, 1H) ppm; ESI MS m/z 223 [M−H]−.

Provenance & Evidence