反应详情

5-(1H-Pyrazol-4-yl)-thiophene-3-carboxylic acid methyl ester (2.8 g, 13.3 mmol) was dissolved in a mixture of methanol (18 mL) and a solution of aqueous sodium hydroxide (1 N, 18 mL) and the mixture stirred at 50° C. for 1.5 hours. The mixture was concentrated under vacuum and acidified with aqueous hydrochloric acid (1N). The resulting precipitate was isolated by filtration and washed with water before drying under vacuum to give the title compound as a white solid (1.77 g). LCMS m/z 195.1 [M+H]+. R.T.=3.23 min (Analytical Method 4). 1H NMR (400 MHz, d6-DMSO): δ 8.1 (s, 1H), 8.0 (m, 2H), 7.45 (s, 1H).

1. concentrationThe mixture was concentrated under vacuum
2. customThe resulting precipitate was isolated by filtration
3. washwashed with water
4. custombefore drying under vacuum