The general procedure for the synthesis of 2,6-dichloro-4-iodophenol from 2,6-dichlorophenol was as follows: 2,6-dichlorophenol (10 g, 61.35 mmol, 1.00 eq.) and N-iodosuccinimide (NIS, 27.6 g, 245.33 mmol, 2.00 eq.) were dissolved in methanol (100 mL) and stirred at room temperature for 1 hour. After completion of the reaction, the mixture was concentrated under reduced pressure. The concentrated residue was redissolved in ethyl acetate (50 mL) and washed with saturated saline (3 x 30 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography using petroleum ether (100%) as eluent to afford 2,6-dichloro-4-iodophenol (10.5 g, 59% yield) as a yellow solid.1H-NMR (300 MHz, CDCl3): δ 9.83 (s, 1H), 7.27 (s, 2H) ppm.
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