Ethanol → 2-Amino-5-fluoro-3-iodopyridine

5 g (44.6 mmol) of 2-amino-5-fluoropyridine, 13.9 g (44.6 mmol) of silver sulphate and 400 ml of ethanol are introduced into a 500 ml two-necked flask equipped with a magnetic stirrer. 11.31 g (44.6 mmol) of powdered iodine are subsequently added in small portions. The stirring is continued at ambient temperature for 24 hours. The insoluble material is removed by filtration and washed with ethanol and the filtrate is concentrated under reduced pressure. The residue thus obtained is taken up in a mixture of ethyl acetate (200 ml) and of a solution of sodium carbonate (200 ml). After separation, the organic phase is washed successively with a 25% aqueous solution of sodium thiosulphate and then with a saturated aqueous solution of sodium chloride, and then dried over sodium sulphate and concentrated under reduced pressure. The resulting solid is purified by silica column chromatography, elution being carried out with a mixture of n-heptane and ethyl acetate. 2.67 g (11.22 mmol) of the expected product are obtained.

1. customequipped with a magnetic stirrer
2. customThe insoluble material is removed by filtration
3. washwashed with ethanol
4. concentrationthe filtrate is concentrated under reduced pressure
5. customThe residue thus obtained
6. customAfter separation
7. washthe organic phase is washed successively with a 25% aqueous solution of sodium thiosulphate
8. dry with materialwith a saturated aqueous solution of sodium chloride, and then dried over sodium sulphate
9. concentrationconcentrated under reduced pressure
10. customThe resulting solid is purified by silica column chromatography, elution
11. additionbeing carried out with a mixture of n-heptane and ethyl acetate

ORD record

ord-d92398f246ea49e39db1cb08f563cf40

Source dataset

uspto-grants-2012_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08143248B2