Water → 2-Ethyl-4-methoxypyrazolo[1,5-a]pyridine

HRID 9188Notes

Reaction equation

HRID 9188 reaction equation
C[C:2](C)([O-:4])C.[K+].C1(C)C=C(C)C=C(C)C=1S([O-])(=O)=O.[NH2:20][N+:21]1[CH:26]=[CH:25][C:24](OC)=[CH:23][C:22]=1[C:29]#[C:30][CH2:31][CH3:32].O.C(OCC)(=O)C>O1CCCC1.CN(C)C=O>[CH2:31]([C:30]1[CH:29]=[C:22]2[C:23]([O:4][CH3:2])=[CH:24][CH:25]=[CH:26][N:21]2[N:20]=1)[CH3:32]

Participants

7

Reactant 4

HCID 962WaterHCID 8857Ethyl AcetateHCID 21984631N-amino-2-(1-butynyl)-4-methoxypyridinium mesitylenesulfonateHCID 23665647Potassium tert-butoxide

Product 1

HCID 219845782-Ethyl-4-methoxypyrazolo[1,5-a]pyridineYield 66.5%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 8028TetrahydrofuranSolvent

Procedure

Potassium tert-butoxide (11.1 g) was added to a solution of N-amino-2-(1-butynyl)-4-methoxypyridinium mesitylenesulfonate (20.7 g) in tetrahydrofuran (300 mL) and N,N-dimethylformamide (15 mL), and the mixture was stirred at room temperature for 1 hour. Water was added while cooling on ice, extraction was performed with ethyl acetate, the extract was washed with brine and dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue was subjected to silica gel column chromatography (200 g), and the title compound (6.44 g) was obtained from the n-hexane:ethyl acetate (3:1) fraction as a yellow oil.

Workup

  1. temperaturewhile cooling on ice, extraction
  2. washthe extract was washed with brine
  3. dry with materialdried over magnesium sulfate
  4. distillationthe solvent was distilled off under reduced pressure

Sources & evidence

ORD record
ord-e725fe37874e4314be98d52b6aead169
Source dataset
uspto-grants-2006_08
Patent number
US07091215B2

Reaction notes

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