Sulfuryl chloride → HCID 20380249, compound

Participants

Reaction Steps

40 g. of methyl 4-acetylamino-3-thiophene carboxylate are dissolved in 1 liter of absolute chloroform, and a solution of 27 g. of sulfuryl chloride in 100 ml. of absolute chloroform is then added dropwise within 20 minutes. The reaction solution is then boiled under reflux for 1 hour. The brownish colored solution obtained is cooled and when its temperature is 10°, 1 liter of ice water is added. The organic solution is then washed with 200 ml. of 5% sodium bicarbonate solution, dried over sodium sulfate, and evaporated to dryness in vacuo. The oily residue is triturated with 100 ml. of ether, whereupon crystallization takes place. The product is suction filtered and recrystallized from ethyl acetate, and methyl 4-acetylamino-5-chloro-3-thiophene carboxylate having a melting point of 119°-121° is obtained. The ethereal filtrate and the mother liquor from the ethyl acetate recrystallization are combined, evaporated to dryness, and the oil that remains is chromatographed on 300 g. of silica gel using methylene chloride/ethyl acetate (4:1) as eluent. An additional portion of methyl 4-acetylamino-5-chloro-3-thiophene carboxylate having a melting point of 119°-121° is obtained.

Provenance & Evidence