Chlorosulfonic acid → 3-methoxythiophene-2-sulfonyl Chloride

Temperature

0 °C

Chlorosulfonic acid (ClSO3H, 2.31 g, 19.62 mmol) was slowly added to a solution of 3-methoxythiophene (2.29 g, 19.62 mmol) in CHCl3 (80 ml) at 0° C. 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-c5fe8eb7035541fd815dbd5e67175091

Source dataset

uspto-grants-2003_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06613804B2