Citric Acid → HCID 15457057, compound

Participants

Reaction Steps

0.9 g (2.8 mmol) of 3-(5-amino-4-chloro-2-fluorophenyl)-1-methyl-6-trifluoromethyl-2(1H)-pyridone and 0.6 g (5.9 mmol) of triethylamine were dissolved in 20 ml of dichloromethane, and 0.7 g (6.1 mmol) of methylsulfonyl chloride was dropwise added thereto under cooling with ice. The mixture was stirred at room temperature for 2 hours and then diluted with an aqueous ammonium chloride solution. The mixture was extracted with ethyl acetate. After washing with water and a saturated sodium chloride aqueous solution, the organic layer was dried over anhydrous magnesium sulfate. Ethyl acetate was distilled off under reduced pressure. Then, the obtained crude crystals of the bissulfone compound were dissolved in 25 ml of ethanol, and 10 ml (5.0 mmol) of a 0.5N sodium hydroxide aqueous solution was added at room temperature, followed by stirring for 1 hour. The mixture was poured into water, acidified with citric acid and extracted with ethyl acetate. After washing with water, the organic layer was dried over anhydrous magnesium sulfate. Ethyl acetate was distilled off under reduced pressure. Then, the obtained crude crystals were washed with n-hexane to obtain 0.80 g (yield: 72%) of the desired product. Melting point: 113-114° C.

Provenance & Evidence