Hydrochloric Acid → 5,6-Dimethyl-2-pyridone

HRID 1994232Notes

Reaction equation

HRID 1994232 reaction equation
C([C:3]1[C:4](=[O:11])[NH:5][C:6]([CH3:10])=[C:7]([CH3:9])[CH:8]=1)#N.Cl>O>[CH3:9][C:7]1[CH:8]=[CH:3][C:4](=[O:11])[NH:5][C:6]=1[CH3:10]

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 5905325,6-Dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile

Product 1

HCID 1197855,6-Dimethyl-2-pyridoneYield 94.3%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
135 °C

Procedure

To a suspension of 3-cyano-5,6-dimethyl-2-pyridone (1-013-02) (12.0 g) in water (293 mL) was added conc. hydrochloric acid (293 mL), and the reaction mixture was reflux with stirring in oil-bath at 135° C. After 3 days, the reaction mixture was cooled, and evaporated under reduced pressure. To the residue (24.75 g) were added chloroform (300 mL) and methanol (15 mL), and the reaction mixture was heated in a water bath at 65° C., and the dissolble material was filtered off. Furthermore, the dissolble material was treated by chloroform (200 mL) and methanol (10 mL) in a similar manner to described above. The combined filtrates were evaporated under reduced pressure. To the obtained residue (13.26 g) were added methanol (150 mL) and potassium carbonate (10 g). After stirred at room temperature for 30 min, the dissolble material was filtered off. The filtrate was evaporated under reduced pressure. To the obtained residue (14.7 g) was added chloroform (200 mL), and the dissolble material was filtered off again. The filtrate was evaporated under reduced pressure to give 5,6-dimethyl-2-pyridone (1-013-03) (9.41 g, 94.3%, m.p.: 202-207° C.)

Workup

  1. temperaturethe reaction mixture was reflux
  2. temperaturethe reaction mixture was cooled
  3. customevaporated under reduced pressure
  4. additionTo the residue (24.75 g) were added chloroform (300 mL) and methanol (15 mL)
  5. temperaturethe reaction mixture was heated in a water bath at 65° C.
  6. filtrationthe dissolble material was filtered off
  7. additionFurthermore, the dissolble material was treated by chloroform (200 mL) and methanol (10 mL) in a similar manner
  8. customThe combined filtrates were evaporated under reduced pressure
  9. additionTo the obtained residue (13.26 g) were added methanol (150 mL) and potassium carbonate (10 g)
  10. stirringAfter stirred at room temperature for 30 min
  11. filtrationthe dissolble material was filtered off
  12. customThe filtrate was evaporated under reduced pressure
  13. additionTo the obtained residue (14.7 g) was added chloroform (200 mL)
  14. filtrationthe dissolble material was filtered off again
  15. customThe filtrate was evaporated under reduced pressure

Sources & evidence

ORD record
ord-1b6f844952964a14831f5f87ba843583
Source dataset
uspto-grants-2010_01
Patent number
US07652141B2

Reaction notes

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