518057-74-4

195609-18-8

518057-74-4

General procedure for the synthesis of 5-amino-2-fluorophenylacetic acid from 2-fluoro-5-nitrophenylacetic acid: to a suspension of 2-(2-fluoro-5-nitrophenyl)acetic acid (15.0 g, 75.3 mmol) in ethanol (800 mL), THF (400 mL), and water (200 mL), ammonium chloride (4.46 g, 83.4 mmol) and powdered iron ( 25.04 g, 405.4 mmol). The reaction mixture was heated at 80 °C for 1 h and the progress of the reaction was monitored by thin layer chromatography (TLC). After complete consumption of raw materials, the reaction mixture was filtered while hot. The filtrate was concentrated under reduced pressure and the crude product was dissolved in ethyl acetate (200 mL) and washed with water (3 x 100 mL). The organic layers were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to give 2-(5-amino-2-fluorophenyl)acetic acid as a gray solid in 48% yield (6.13 g), which was used directly in the next reaction.