192508-36-4

General procedure for the synthesis of 3-nitro-4-fluorophenylacetic acid from 4-fluorophenylacetic acid: to a solution of concentrated sulfuric acid (20 mL) of 4-fluorophenylacetic acid (3 g, 19.46 mmol) was added drop by drop of nitric acid (0.913 mL, 20.44 mmol) at 0 °C, and the reaction was stirred for 1 hour. After completion of the reaction, the mixture was slowly poured into ice water and extracted with dichloromethane (DCM, 2 x 20 mL). The organic phases were combined, washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated to dryness under reduced pressure to give 3-nitro-4-fluorophenylacetic acid (3.48 g, 90% yield). Mass spectrum (ESI) m/z: 198.1 ([M-H]+).

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