Iodine → 2-Amino-5-chloro-3-iodopyridine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a mixed solution of 2-amino-5-chloropyridine (2.6 g, 0.020 mol) in acetic acid/water (7.8 mL/1.8 mL) that cooled with ice bath, conc.sulfuric acid (0.26 mL, 4.9 mmol) was added dropwise, and then periodic acid (0.95 g, 4.2 mmol) and iodine (2.0 g, 8.0 mmol) were added. The reaction mixture was stirred at 80° C. for 6 h. Cooled to ambient temperature, the reaction mixture was poured into ice water, and neutralized by aqueous 5M sodium hydroxide solution. After removal of the precipitate by filtration, the filtrate was extracted with ethyl acetate. The organic layer was washed with saturated sodium thiosulfate solution, aqueous 1M sodium hydroxide solution and brine then dried over sodium sulfate and concentrated to afford 2-amino-5-chloro-3-iodopyridine as solid (4.4 g, y. 85%).

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