Ethanol → 4,5,6,7-Tetrahydropyrazolo[1,5-a]pyridin-2-amine

HRID 1378669Notes

Reaction equation

HRID 1378669 reaction equation
[OH-].[K+].Cl.NO.CC1[N:8]([C:13]2[CH:21]=[C:16]3[CH2:17]N[CH2:19][CH2:20][N:15]3[N:14]=2)C(C)=CC=1.[CH2:22](O)C>O>[NH2:8][C:13]1[CH:21]=[C:16]2[CH2:17][CH2:22][CH2:19][CH2:20][N:15]2[N:14]=1

Participants

6

Reactant 4

HCID 702Ethanol2×HCID 14797Potassium HydroxideHCID 443297Hydroxyamine hydrochlorideHCID 22912799HCID 22912799, compound

Product 1

HCID 543166624,5,6,7-Tetrahydropyrazolo[1,5-a]pyridin-2-amine

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

8.19 g (146 mmole) potassium hydroxide, dissolved in 122 ml water and 122 ml ethanol, was added to 19.19 g (292 mmole) hydroxylamine hydrochloride in 200 ml ethanol. The mixture was stirred for 15 minutes, 12.5 g (58 mmole) 2-(2,5-dimethyl-1-pyrrolyl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine added and heated for 30 hours under reflux. After removal of the ethanol the mixture was treated with ethyl acetate, filtered from solid material and the aqueous phase saturated with sodium chloride and extracted with ethyl acetate. The organic phase was with washed with saturated aqueous sodium chloride, dried over sodium sulfate and concentrated. The crude product was purified by silica gel column chromatography (ethyl acetate/methanol).

Workup

  1. temperatureheated for 30 hours
  2. temperatureunder reflux
  3. customAfter removal of the ethanol the mixture
  4. additionwas treated with ethyl acetate
  5. filtrationfiltered from solid material
  6. extractionthe aqueous phase saturated with sodium chloride and extracted with ethyl acetate
  7. washwith washed with saturated aqueous sodium chloride
  8. dry with materialdried over sodium sulfate
  9. concentrationconcentrated
  10. customThe crude product was purified by silica gel column chromatography (ethyl acetate/methanol)

Sources & evidence

ORD record
ord-3e5d03e0ef2b405ab042168a876cd0ba
Source dataset
uspto-grants-1997_09
Patent number
US05668278

Reaction notes

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