Water → 4H,5H,6H,7H-pyrazolo(1,5-a)pyrimidine-3-carbaldehyde

HRID 349560Notes

Reaction equation

HRID 349560 reaction equation
P(Cl)(Cl)(Cl)=O.[N:6]1[N:10]2[CH2:11][CH2:12][CH2:13][N:14](C=O)[C:9]2=[CH:8][CH:7]=1.O.[C:18](=O)([O-])[O-:19].[Na+].[Na+]>CN(C)C=O>[N:6]1[N:10]2[CH2:11][CH2:12][CH2:13][NH:14][C:9]2=[C:8]([CH:18]=[O:19])[CH:7]=1

Participants

6

Reactant 4

HCID 962WaterHCID 10340Sodium CarbonateHCID 24813Phosphorus oxychlorideHCID 150777426,7-Dihydropyrazolo[1,5-a]pyrimidine-4(5H)-carbaldehyde

Product 1

HCID 1357327674H,5H,6H,7H-pyrazolo(1,5-a)pyrimidine-3-carbaldehyde

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent2×

Conditions

Temperature
80 °C

Procedure

To N,N-dimethylformamide (307 ml) was added dropwise phosphorus oxychloride (123 ml) under ice-cooling. To the mixture was added a solution of 4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-4-carbaldehyde (100 g) in N,N-dimethylformamide (200 ml) under ice-cooling. The reaction mixture was stirred at 80° C. for 2 hours. After cooling, water was added to the reaction mixture, and the mixture was neutralized with sodium carbonate. The mixture was extracted with chloroform. The organic layer was dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. The residue was triturated with hexane and dried in vacuo to give 4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-3-carbaldehyde (65 g) as a solid.

Workup

  1. temperaturecooling
  2. temperaturecooling
  3. temperatureAfter cooling
  4. extractionThe mixture was extracted with chloroform
  5. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo
  8. customThe residue was triturated with hexane
  9. customdried in vacuo

Sources & evidence

ORD record
ord-455160dd198f431c822560880b1c1143
Source dataset
uspto-grants-2007_02
Patent number
US07179801B2

Reaction notes

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