反应详情

温度

-75 °C

To a solution of 2,3-dibromothiophene (12.6 g, 50 mmol) in THF abs. (125 mL) was added at −75° C. n-BuLi (1.6M/hexane, 31 mL) over 30 minutes. The reaction mixture was further stirred at −75° C. for 30 minutes, and p-toluenesulfonic acid-2-methoxyethylester (11.8 g, 50 mmol) was added dropwise over 1 h. The mixture stirred for 2 h without cooling, quenched with brine, and extracted with ether. The organics were washed, dried, and concentrated. The residue was chromatographed on silica gel using heptane/ethyl acetate as eluent to obtain 3-bromo-2-(2-methoxy-ethyl)-thiophene (1.8 g) as a colorless liquid. MS (EI): 221.1 (M)

1. stirringThe mixture stirred for 2 h
2. temperaturewithout cooling
3. customquenched with brine
4. extractionextracted with ether
5. washThe organics were washed
6. customdried
7. concentrationconcentrated
8. customThe residue was chromatographed on silica gel