Sulfuric Acid → HCID 178526541, compound

Participants

Reaction Conditions

Reaction Steps

6-[2-Cyclopropyl-5-(2,4-difluorophenyl)-1H-imidazol-4-yl]-3-nitro-pyridin-2-amine (5.51 g, 15.41 mmol) is suspended in dimethyl sulfoxide (DMSO, 32 mL), water (25 mL), and concentrated H2SO4 (6 mL). The suspension is cooled at 0° C. and sodium nitrite (2.13 g, 30.81 mmol) is added portionwise at such a rate that the temperature is maintained below 5° C. The mixture is stirred at 0° C. for 30 min, and then is allowed to warm to RT, and is stirred until liquid chromatography/mass spectrometry (LC/MS) shows complete conversion of the starting material (1 hour). A 0.8 M aqueous solution of sodium phosphate monobasic (200 mL) is added to the mixture. A yellow suspension is formed. Aqueous 1 N NaOH is then added until the pH rises to 8. The mixture is stirred for 30 h, filtered, and the solid is rinsed with water, and then dried under reduced pressure to afford the title compound (4.53 g, 82%). LC-ES/MS m/z 358.9 (M+1).

Provenance & Evidence