Chlorosulfonic acid → 3-methoxythiophene-2-sulfonyl Chloride

Temperature

0 °C

Chlorosulfonic acid (ClSO3H, 2.31 g, 19.62 mmol) was slowly added at 0° C. to a solution of 3-methoxythiophene (2.29 g, 19.62 mmol) in CHCl3 (80 ml) The resulting mixture was stirred at 0° C. for 30 min. The solvent was evaporated under reduced pressure, at room temperature, the residue was suspended in POCl3 (15 ml, 156.96 mmol), and PCl5 (8.2 g, 39.24 mmol) was added slowly. The reaction was stirred at 60° C. for 18 h, then cooled to room temperature and poured onto crushed ice (200 g). The aqueous mixture was extracted with CHCl3 (2×150 ml) and the combined organic layers was dried (MgSO4). The solid was removed by filtration and the filtrate was concentrated to give 3-methoxy-2-thiophenesulfonyl chloride as a brown oil (1.81 g, 43% yield).

1. customThe solvent was evaporated under reduced pressure, at room temperature
2. stirringThe reaction was stirred at 60° C. for 18 h
3. temperaturecooled to room temperature
4. additionpoured
5. extractionThe aqueous mixture was extracted with CHCl3 (2×150 ml)
6. dry with materialthe combined organic layers was dried (MgSO4)
7. customThe solid was removed by filtration
8. concentrationthe filtrate was concentrated

ORD record

ord-9dcc4f934d794914ae4decd0af24f056

Source dataset

uspto-grants-1996_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05571821