Hydrochloric Acid → 3-Methyl-1-(2-pyridinyl)-1,9-dihydro-4H-pyrazolo[3,4-b]quinolin-4-one

HRID 497966Notes

Reaction equation

HRID 497966 reaction equation
Cl[C:2]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=2)[N:5]=[C:4]2[N:12]([C:16]3[CH:21]=[CH:20][CH:19]=[CH:18][N:17]=3)[N:13]=[C:14]([CH3:15])[C:3]=12.Cl.C([OH:25])C>>[CH3:15][C:14]1[C:3]2[C:2](=[O:25])[C:11]3[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=3)[NH:5][C:4]=2[N:12]([C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][N:17]=2)[N:13]=1

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 702EthanolHCID 223201094-Chloro-3-methyl-1-(2-pyridinyl)-1H-pyrazolo[3,4-b]quinoline

Product 1

HCID 1358480443-Methyl-1-(2-pyridinyl)-1,9-dihydro-4H-pyrazolo[3,4-b]quinolin-4-oneYield 79%

Procedure

To a solution of 4-chloro-3-methyl-1-(2-pyridinyl)-1H-pyrazolo[3,4-b]quinoline (34.9 g, 0.12 mol) in ethanol (500 mL) was added 6N hydrochloric acid (50 mL, 0.30 mol), and the mixture was heated and under reflux for 2 hours. The solution was cooled to room temperature, and the reaction solvent was concentrated and evaporated under reduced pressure. The residue was made basic by the addition of an aqueous sodium hydroxide solution, and organic matter was extracted with chloroform. The extract was washed with saturated brine and water, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue thus obtained was purified by silica gel column chromatography (chloroform:methanol=95:5) to give the title compound (25.8 g, 79% yield).

Workup

  1. temperaturethe mixture was heated
  2. temperatureunder reflux for 2 hours
  3. concentrationthe reaction solvent was concentrated
  4. customevaporated under reduced pressure
  5. additionThe residue was made basic by the addition of an aqueous sodium hydroxide solution, and organic matter
  6. extractionwas extracted with chloroform
  7. washThe extract was washed with saturated brine and water
  8. dry with materialdried over anhydrous magnesium sulfate
  9. customthe solvent was evaporated under reduced pressure
  10. customThe residue thus obtained
  11. customwas purified by silica gel column chromatography (chloroform:methanol=95:5)

Sources & evidence

ORD record
ord-a7f2740822c44b8d807ef76c6060e8ad
Source dataset
uspto-grants-2005_09
Patent number
US06949648B2

Reaction notes

Loading…