反应详情

Phosphorous pentachloride (2.08 g, 40 mmol) was added to a solution of 5-benzylthiophene-2-sulfonic acid in phosphorous oxychloride (6.0 g, 40 mmol) at 0° C. The reaction mixture was kept at 50° C. for 1 h, cooled to room temperature, then poured onto crushed ice (50 g) and extracted with ethyl acetate (2×30 ml). Removal of the solvent under reduced pressure gave a crude product, which was purified by column chromatography using 3% ethyl acetate in hexane to give 2-benzylthiophene-5-sulfonyl chloride (0.6 g, 39% yield).

1. additionpoured
2. extractionextracted with ethyl acetate (2×30 ml)
3. customRemoval of the solvent under reduced pressure
4. customgave a crude product, which
5. customwas purified by column chromatography