Iodine → 2-Iodo-6-(trifluoromethyl)pyridin-3-amine

Participants

Reaction Steps

1.56 g (6.17 mmol) of iodine is added, in several portions, to a mixture, stirred under argon at 20° C., of 1 g (6.17 mmol) of 3-amino-6-trifluoromethylpyridine and 1.25 g (6.17 mmol) of silver sulfate in 40 mL of ethanol. Stirring is maintained for 18 hours. The insoluble matter is removed by filtration and is washed with ethanol, the filtrate is concentrated at reduced pressure, and the residue is taken up in 100 mL of dichloromethane. The organic phase is washed successively with 20 mL of 5% aqueous solution of sodium hydroxide, 40 mL of water and 20 mL of saturated aqueous solution of sodium chloride, dried over sodium sulfate, concentrated at reduced pressure, and then purified by chromatography on a silica column (eluents: heptane-ethyl acetate). In this way we isolate 1.17 g of the expected product, which is used as it is in the rest of the synthesis.

Provenance & Evidence