Acetic Anhydride → 1-(2-Phenylpyrazolo[1,5-a]pyridin-3-yl)-1-ethanone

HRID 1029408Notes

Reaction equation

HRID 1029408 reaction equation
[C:1]1([C:7]2[CH:15]=[C:10]3[CH:11]=[CH:12][CH:13]=[CH:14][N:9]3[N:8]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[C:16](OC(=O)C)(=[O:18])[CH3:17]>S(=O)(=O)(O)O.[OH-].[Na+]>[C:1]1([C:7]2[C:15]([C:16](=[O:18])[CH3:17])=[C:10]3[CH:11]=[CH:12][CH:13]=[CH:14][N:9]3[N:8]=2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

5

Reactant 2

HCID 7918Acetic AnhydrideHCID 156203422-Phenylpyrazolo[1,5-a]pyridine

Product 1

HCID 107049561-(2-Phenylpyrazolo[1,5-a]pyridin-3-yl)-1-ethanoneYield 47.7%

Reagents, catalysts & solvents 2

HCID 1118Sulfuric AcidCatalystHCID 14798Sodium HydroxideSolvent

Procedure

2-Phenylpyrazolo[1,5-a]pyridine (2.00 g) was added to a stirred solution of acetic anhydride (4.20 g) and two drops of sulfuric acid at room temperature. After being stirred under reflux for 14 hours, the reaction mixture was poured onto 80 ml of 4 N NaOH aqueous solution and extracted with chloroform (30 ml×2). The extracts were combined and washed with water (30 ml), saturated sodium chloride aqueous solution (30 ml), then dried over magnesium sulfate and evaporated in vacuo. The residual crystals were recrystallized from diisopropyl ether to give 2-phenyl-3-acetylpyrazolo-[1,5-a]pyridine (1.16 g).

Workup

  1. temperatureunder reflux for 14 hours
  2. extractionextracted with chloroform (30 ml×2)
  3. washwashed with water (30 ml), saturated sodium chloride aqueous solution (30 ml)
  4. dry with materialdried over magnesium sulfate
  5. customevaporated in vacuo
  6. customThe residual crystals were recrystallized from diisopropyl ether

Sources & evidence

ORD record
ord-822cc392bbe747b69933a295697522b0
Source dataset
uspto-grants-1992_04
Patent number
US05102878

Reaction notes

Loading…