General procedure for the synthesis of 2-(4-bromo-3-fluorophenyl)acetic acid from 3-fluoro-4-bromophenylacetonitrile: 3-fluoro-4-bromophenylacetonitrile (0.78 g, 3.64 mmol) was dissolved in a mixture of sulphuric acid (5 mL) and water (5 mL), and the reaction was stirred for 16 hours at 100 °C. The progress of the reaction was monitored by LCMS and after confirming complete consumption of the raw materials, the reaction mixture was dissolved in water (20 mL) and extracted with ethyl acetate (20 mL). The organic layers were combined, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure to afford 2-(4-bromo-3-fluorophenyl)acetic acid (0.7 g, 2.046 mmol, 56.1% yield) as a white solid. The product was characterized by 1H NMR (400 MHz, CD3OD): δ 7.53 (t, J = 7.8 Hz, 1H), 7.16 (dd, J = 9.8, 1.9 Hz, 1H), 7.02 (d, J = 8.0 Hz, 1H), 3.61 (s, 2H).
