Sulfuric Acid → HCID 178500118, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 2-[4-(6-amino-5-nitro-2-pyridyl)-5-(2,4-difluorophenyl)-1H-imidazol-2-yl]-2-methyl-propanoate (56 g, 134.17 mmol) in dimethyl sulfoxide (DMSO, 400 mL) and water (320 mL), is added sulfuric acid 95-97% (80 mL) dropwise. Then the mixture is cooled to 0° C. To the above mixture a solution of sodium nitrite (18.70 g, 268.35 mmol) in water (80 mL) is added dropwise over 15 min at 0° C. The reaction mixture is stirred for 20 min at that temperature and then the cooling bath is removed and the temperature is allowed to rise to RT. To the reaction mixture is added a 0.8 M aqueous solution of buffered sodium phosphate monobasic (1200 mL, pH=6). A yellow suspension appears. This suspension is stirred at RT for 1 h. The solid is filtered, washed with water, and dried in the oven to afford the title compound as an orange solid (49.5 g, 88%). LC-ES/MS m/z 419 (M+1).

Provenance & Evidence