1022961-12-1

General procedure for the synthesis of 2-amino-3-chloro-5-fluorobenzoic acid from 2-amino-5-fluorobenzoic acid: a mixture of 2-amino-5-fluorobenzoic acid (5.0 g, 32.26 mmol), N-chlorosuccinimide (NCS, 4.39 g, 32.9 mmol), and N,N-dimethylformamide (DMF, 30 mL) was stirred and reacted at room temperature for 16 hours. After completion of the reaction, the reaction solution was diluted with water (100 mL) and extracted with ethyl acetate (3 x 100 mL). The organic phases were combined, washed with saturated aqueous sodium chloride, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The concentrated residue was stirred with dichloromethane (100 mL) for 10 min and filtered to afford the target product 2-amino-3-chloro-5-fluorobenzoic acid (3.4 g, 56% yield) as a gray solid.LC-MS (ESI): m/z = 190.0 ([M + H]+).

[1] Bioorganic and Medicinal Chemistry, 2008, vol. 16, # 6, p. 3163 - 3170
[2] Patent: US2016/244432, 2016, A1. Location in patent: Paragraph 0232; 0233