Phosphorus oxychloride → 2-Chloro-5-nitropyridine-3-carboxylic acid

HRID 1078552Notes

Reaction equation

HRID 1078552 reaction equation
O[C:2]1[N:10]=[CH:9][C:8]([N+:11]([O-:13])=[O:12])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].P(Cl)(Cl)([Cl:16])=O>>[Cl:16][C:2]1[N:10]=[CH:9][C:8]([N+:11]([O-:13])=[O:12])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5]

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 178524577HCID 178524577, compound

Product 1

HCID 125426642-Chloro-5-nitropyridine-3-carboxylic acid

Procedure

A solution of 2-hydroxy-5-nitronicotinic acid (9.2 g, 0.05 mol) in phosphorus oxychloride (25 ml) was refluxed for 5 hours. The solvent was removed in vacuo and the residue dissolved in a mixture of tetrahydrofuran and ether. After cooling the solution in an ice bath, water was cautiously added dropwise with stirring until a clean separation of layers was obtained. The organic layer was washed with water and a saturated sodium chloride solution, dried (anhydrous magnesium sulfate) and concentrated. Recrystallization from ether gave 6.94 g (69% of theory) of pure product, m.p. 135° C. (dec).

Workup

  1. customThe solvent was removed in vacuo
  2. dissolutionthe residue dissolved in a mixture of tetrahydrofuran and ether
  3. temperatureAfter cooling the solution in an ice bath
  4. additionwater was cautiously added dropwise
  5. customwas obtained
  6. washThe organic layer was washed with water
  7. dry with materiala saturated sodium chloride solution, dried (anhydrous magnesium sulfate)
  8. concentrationconcentrated
  9. customRecrystallization from ether
  10. customgave 6.94 g (69% of theory) of pure product, m.p. 135° C. (dec)

Sources & evidence

ORD record
ord-53f1f62e75934da2bd1d38e177bd1d76
Source dataset
uspto-grants-1996_08
Patent number
US05550122

Reaction notes

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