Citric Acid → HCID 15457048, compound

Participants

Reaction Steps

9.3 g (32 mmol) of 3-(4-chloro-2-fluorophenyl)-6-trifluoromethyl-2H-pyran-2-one was added to 160 ml of methanol, and 3.8 g (48 mmol) of a 40% methylamine/methanol solution was dropwise added under cooling with ice, followed by stirring for 2 hours under cooling with ice. This reaction solution was acidified by an addition of a 10% citric acid aqueous solution and then extracted with ethyl acetate, followed by washing with water. The organic layer was dried over anhydrous magnesium sulfate, and then, the solvent was distilled off. The obtained residue was dissolved in 160 ml of toluene, and 0.4 g (2.1 mmol) of p-toluenesulfonic acid was added thereto, followed by refluxing for 4 hours. After cooling, the reaction solution was washed with water. Then, the organic layer was dried over anhydrous magnesium sulfate, and then, the solvent was distilled off. The obtained residue was purified by silica gel column chromatography to obtain 5.7 g (19 mmol) of the desired product. Melting point: 103-104° C.

Provenance & Evidence