1258298-05-3

Step b: Synthesis of 2,6-dichloro-4-cyanobenzoic acid Methyl 2,6-dichloro-4-cyanobenzoate (620 mg, 2.6 mmol) was suspended in pyridine (5 mL) and anhydrous lithium iodide (1000 mg, 8 mmol) was added. The reaction mixture was heated and stirred at reflux for 1 h, followed by concentration under reduced pressure to remove the pyridine. The residue was acidified to pH 2-3 with 2N hydrochloric acid under cooling in an ice bath.The precipitated solid was filtered, washed with water and dried to afford 2,6-dichloro-4-cyanobenzoic acid (380 mg, 86% yield) as a light brown solid.1H NMR (400 MHz, DMSO-d6): δ 8.23 (s, 2H).

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