Sodium Hydroxide → HCID 17858942, compound

Participants

Reaction Steps

In DMF (10 ml) were dissolved 4-fluorobenzo(d)isothiazole-3-carboxylic acid (240 mg, 1.22 mmol), ethyl 4-amino-5-chloro-2-fluorophenylacetate (282 mg, 1.22 mmol), HOBt (313 mg, 2.32 mmol), EDC HCl (351 mg, 1.83 mmol) and DMAP (catalytic amount). The resulting solution was stirred for 4 days at room temperature. The reaction mixture was poured in 1M HCl, followed by extraction with ethyl acetate. The extract was washed with saturated brine, dried over anhydrous magnesium sulfate and distilled under reduced pressure to remove the solvent. The residue was purified by silica gel column chromatography (middle pressure chromatography system from Yamazen, chloroform, 8 ml/min, φ 15 mm×300 mm). To the resulting ester were added THF (12 ml) and 0.25M NaOH (7.32 ml, 1.83 mmol), followed by stirring at room temperature for 4 hours. The reaction mixture was poured in 1M HCl to acidify the mixture. The crystals thus precipitated were collected by filtration under reduced pressure, washed with water, and dried under reduced pressure to give (5-chloro-2-fluoro-4-((4-fluoro-3-benzo(d)isothiazolylcarbonyl)amino)phenyl)acetic acid (105 mg, 22%) as a colorless solid.

Provenance & Evidence