Hydrochloric Acid → 2-bromo-4-[(2-{1-[5-(4-tert-butylphenyl)-4-hydroxy-1-methyl-1H-pyrazol-3-yl]ethylidene}hydrazino)carbonyl]benzoic acid

Participants

Reaction Conditions

Reaction Steps

To methyl 2-bromo-4-[(2-{1-[5-(4-tert-butylphenyl)-4-hydroxy-1-methyl-1H-pyrazol-3-yl]ethylidene}hydrazino)carbonyl]benzoate (0.455 mmol, 239.8 mg), methanol (20 mL) was added, and 1 M aqueous sodium hydroxide (2.3 mmol, 2.3 mL) was added. After 5 hours of stirring at 50° C., 14 hours of stirring at room temperature and 4 hours of stirring at 50° C., 1 M hydrochloric acid (2.3 mmol, 2.3 mL) and water were added. The precipitated solid was recovered by filtration, washed with water and dried by means of a vacuum pump to give the crude desired product as a yellow solid (203.8 mg). Further, 178 mg of the crude desired product was dissolved in THF (35 mL) and stirred at room temperature for 2 days. The insolubles were filtered off, and the filtrate was concentrated and dried by means of a vacuum pump. After addition of chloroform, the precipitated solid was recovered by filtration and dried by means of a vacuum pump to give the desired product as a pale yellow solid (150.9 mg, yield 74%).

Provenance & Evidence