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

HRID 1690051Notes

Reaction equation

HRID 1690051 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([F:8])=[CH:4][N:3]=1.C(O)C.[I:12]I>C(OCC)(=O)C.C(=O)([O-])[O-].[Na+].[Na+].S([O-])([O-])(=O)=O.[Ag+2]>[NH2:1][C:2]1[C:7]([I:12])=[CH:6][C:5]([F:8])=[CH:4][N:3]=1

Participants

7

Procedure

5 g (44.6 mmol) of 2-amino-5-fluoropyridine, 13.9 g (44.6 mmol) of silver sulfate and 400 mL of ethanol are put in a 500-mL two-necked flask equipped with a magnetic stirrer. Then 11.31 g (44.6 mmol) of iodine powder is added, in small portions. It is stirred at room temperature for 24 hours. The insoluble matter is removed by filtration and is washed with ethanol, and the filtrate is concentrated at reduced pressure. The residue thus obtained is taken up in a mixture of ethyl acetate (200 mL) and sodium carbonate solution (200 mL). After separation, the organic phase is washed successively with a 25% aqueous solution of sodium thiosulfate then with a saturated aqueous solution of sodium chloride, then it is dried over sodium sulfate and concentrated at reduced pressure. The resultant solid is purified by chromatography on a silica column, eluting with a mixture of n-heptane and ethyl acetate. We obtain 2.67 g (11.22 mmol) of the expected product.

Workup

  1. customequipped with a magnetic stirrer
  2. customThe insoluble matter is removed by filtration
  3. washis washed with ethanol
  4. concentrationthe filtrate is concentrated at reduced pressure
  5. customThe residue thus obtained
  6. customAfter separation
  7. washthe organic phase is washed successively with a 25% aqueous solution of sodium thiosulfate
  8. dry with materialwith a saturated aqueous solution of sodium chloride, then it is dried over sodium sulfate
  9. concentrationconcentrated at reduced pressure
  10. customThe resultant solid is purified by chromatography on a silica column
  11. washeluting with a mixture of n-heptane and ethyl acetate

Sources & evidence

ORD record
ord-5f286d74ae464bc88e84235c9b8f1e6c
Source dataset
uspto-grants-2012_04
Patent number
US08153650B2

Reaction notes

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