Sodium Bicarbonate → HCID 178469296, compound

Participants

Reaction Steps

A solution of 3-(ethoxycarbonyl)-4-(3-methyl-1H-pyrazol-4-yl)but-3-enoic acid (20 g, 84 mmol) in acetic anhydride (80 mL), sodium acetate (13.8 g, 168 mmol) was added at room temperature and the mixture was heated at reflux for 4 hours. The reaction mixture was cooled to room temperature, basified (pH˜9) using aqueous NaHCO3 solution and extracted with ethyl acetate (2×100 mL). The combined organic layers were washed with water (50 mL), saturated aqueous NaCl (50 mL), dried over anhydrous Na2SO4 and concentrated to obtain crude product; which was purified by column chromatography (100-200 mesh silica gel) using 6-8% ethyl acetate in pet-ether as eluents to afford ethyl 3-methyl-7-hydroxy-1H-indazole-5-carboxylate (10 g, 40%) as orange solid. 1H NMR (CDCl3) δ 8.25 (s, 1H), 7.9 (s, 1H), 4.4 (q, 2H), 2.75 (s, 3H), 2.6 (s, 3H), 2.4 (s, 3H), 1.4 (t, 3H).

Provenance & Evidence