Benzene → HCID 59631668, compound

Participants

Reaction Steps

5-(1-(2-Chlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-5-yl)thiophene-2-sulfonic acid (˜3.2 mmol from previous step) was combined with benzene (5.0 mL) in a reaction vial. This mixture was treated with thionyl chloride (5.0 mL, 69 mmol) and a catalytic amount of dimethylformamide (0.1 mL). The reaction was then heated to reflux in an oil bath. After refluxing for 1 hour the reaction mixture was concentrated under reduced pressure to afford a yellow oil that partially solidified under reduced pressure. This crude material was purified by flash column chromatography eluting with a gradient from 10% to 30% EtOAc/hexane. Product-containing fractions were collected and concentrated to afford 5-(1-(2-chlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-5-yl)thiophene-2-sulfonyl chloride as a pale yellow oil. The mostly pure material was carried on to subsequent transformations without further purification.

Provenance & Evidence