Phosphorus oxychloride → 4-Chloro-3-methoxy-2-methylpyridine

HRID 649209

Reaction equation

HRID 649209 reaction equation
[CH3:1][O:2][C:3]1[C:8](=O)[CH:7]=[CH:6][NH:5][C:4]=1[CH3:10].P(Cl)(Cl)([Cl:13])=O>>[Cl:13][C:8]1[CH:7]=[CH:6][N:5]=[C:4]([CH3:10])[C:3]=1[O:2][CH3:1]

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 3234243-Methoxy-2-methyl-1H-pyridin-4-one

Product 1

HCID 105830464-Chloro-3-methoxy-2-methylpyridine

Procedure

3-Methoxy-2-methyl-4(1H)-pyridone (5.6 g) was suspended in phosphorus oxychloride (50 ml), refluxed for 10 hours, and concentrated. To the resultant residue was added toluene and the residual phosphorus oxychloride was evaporated under reduced pressure. To the resultant oily substance were added chloroform and water and the chloroform layer was separated. The aqueous layer was made alkaline with potassium carbonate and extracted with chloroform. The chloroform solutions thus obtained were combined, washed with water, dried, and evaporated. The residue was purified by column chromatography on silica gel, to give 4-chloro-3-methoxy-2-methylpyridine (4.8 g) as a light brown oil.

Workup

  1. temperaturerefluxed for 10 hours
  2. concentrationconcentrated
  3. additionTo the resultant residue was added toluene
  4. customthe residual phosphorus oxychloride was evaporated under reduced pressure
  5. additionTo the resultant oily substance were added chloroform and water
  6. customthe chloroform layer was separated
  7. extractionextracted with chloroform
  8. customThe chloroform solutions thus obtained
  9. washwashed with water
  10. customdried
  11. customevaporated
  12. customThe residue was purified by column chromatography on silica gel

Sources & evidence

ORD record
ord-f14632ad3c684d5caf7fc9c6037bd456
Source dataset
uspto-grants-1988_04
Patent number
US04738975

Linked notes

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