反应详情

Br2 (0.665 mL, 12.9 mmol) was added dropwise to a solution of (5-methylthiophen-2-yl)-oxo-acetic acid (1.05 g, 6.15 mmol) and sodium acetate (757 mg, 9.23 mmol) in 10 ml of glacial acetic acid and stirred at room temperature for 6.5 hours. The reaction mixture was poured into 150 ml water and extracted with diethyl ether (2×75 ml). The combined diethyl ether layers were extracted with aqueous Na2S2O3, the organic layer was then dried over sodium sulfate, and concentrated under vacuum to provide crude (4-bromo-5-methylthiophen-2-yl)-oxo-acetic acid (1.40 g, 91%). 1H NMR (300 MHz, CDCl3) δ8.35 (1H, s), 2.54 (3H, s).

1. extractionextracted with diethyl ether (2×75 ml)
2. extractionThe combined diethyl ether layers were extracted with aqueous Na2S2O3
3. dry with materialthe organic layer was then dried over sodium sulfate
4. concentrationconcentrated under vacuum