Isoamyl Nitrite → Ethyl 1-phenyl-1H-pyrazole-4-carboxylate

HRID 914450Notes

Reaction equation

HRID 914450 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[C:7](N)=[N:8][N:9]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH:10]=1)=[O:5])[CH3:2].N(OCCC(C)C)=O>O1CCCC1>[CH2:1]([O:3][C:4]([C:6]1[CH:7]=[N:8][N:9]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH:10]=1)=[O:5])[CH3:2]

Participants

4

Reactant 2

HCID 8053Isoamyl NitriteHCID 14590586Ethyl 3-amino-1-phenyl-1H-pyrazole-4-carboxylate

Product 1

HCID 13802154Ethyl 1-phenyl-1H-pyrazole-4-carboxylateYield 71%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
65 °C

Procedure

3-Amino-1-phenyl-1H-pyrazole-4-carboxylic acid ethyl ester (64.8 g) synthesized in Reference Example 15 was dissolved in tetrahydrofuran (500 mL), isoamyl nitrite (98.5 g) was added, and the mixture was stirred at 65° C. for 3 hr. After cooling, the reaction mixture was concentrated under reduced pressure. Hexane (500 mL) was added to the residue, and the residue was washed by suspending and filtered. The obtained solid was vacuum dried to give the title compound (43.0 g) as a white solid.

Workup

  1. temperatureAfter cooling
  2. concentrationthe reaction mixture was concentrated under reduced pressure
  3. additionHexane (500 mL) was added to the residue
  4. washthe residue was washed
  5. filtrationfiltered
  6. customdried

Sources & evidence

ORD record
ord-e2c5b276dead48f1a5abf351ff8047a8
Source dataset
uspto-grants-2011_09
Patent number
US08026370B2

Reaction notes

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