Iodine → 3-Iodo-5-(trifluoromethyl)pyridin-2-amine

2 g (12.34 mmol) of 2-amino-5-trifluoromethylpyridine, 3.85 g (12.34 mmol) of silver sulfate and 80 mL of ethanol are introduced into a 500 mL two-necked flask equipped with a magnetic stirrer. 3.13 g (12.34 mmol) of iodine powder are then added portionwise to the reaction medium stirred at room temperature. The reaction mixture is then stirred at room temperature for 48 hours. The resulting yellow suspension is filtered, the precipitate is rinsed with ethanol and the filtrate is evaporated under reduced pressure. The residue is taken up in 100 mL of dichloromethane. This solution is washed successively with 20 mL of aqueous 5% sodium hydroxide solution, 20 mL of water and 20 mL of saturated aqueous sodium chloride solution and then dried over sodium sulfate and concentrated under reduced pressure. The resulting solid is purified by chromatography on a column of silica, eluting with a mixture of n-heptane and ethyl acetate. 1.71 g of product are obtained in the form of a pink powder.

1. customequipped with a magnetic stirrer
2. stirringThe reaction mixture is then stirred at room temperature for 48 hours
3. filtrationThe resulting yellow suspension is filtered
4. washthe precipitate is rinsed with ethanol
5. customthe filtrate is evaporated under reduced pressure
6. washThis solution is washed successively with 20 mL of aqueous 5% sodium hydroxide solution, 20 mL of water and 20 mL of saturated aqueous sodium chloride solution
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe resulting solid is purified by chromatography on a column of silica
10. washeluting with a mixture of n-heptane and ethyl acetate

ORD record

ord-e707516d1f85444faf87cf1934e1694c

Source dataset

uspto-grants-2011_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08044066B2