(2,3-Dichlorophenyl)hydrazine → 1-(2,3-dichlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-5-amine

HRID 1842884Notes

Reaction equation

HRID 1842884 reaction equation
[F:1][C:2]([F:9])([F:8])[C:3](=O)[CH2:4][C:5]#[N:6].[Cl:10][C:11]1[C:16]([Cl:17])=[CH:15][CH:14]=[CH:13][C:12]=1[NH:18][NH2:19]>C(O)C>[Cl:10][C:11]1[C:16]([Cl:17])=[CH:15][CH:14]=[CH:13][C:12]=1[N:18]1[C:5]([NH2:6])=[CH:4][C:3]([C:2]([F:9])([F:8])[F:1])=[N:19]1

Participants

4

Reactant 2

HCID 600691(2,3-Dichlorophenyl)hydrazineHCID 138435404,4,4-Trifluoro-3-oxobutanenitrile

Product 1

HCID 708164711-(2,3-dichlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-5-amineYield 39.65%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a stirred suspension of 4,4,4-trifluoro-3-oxobutanenitrile (20 g, 145.98 mmol, 1.0 eq.) in ethanol (200 mL) was added (2,3-dichlorophenyl)hydrazine (47.5 g, 145.98 mmol, 1.0 eq) and refluxed for 3 h. Ethanol was evaporated, the residue diluted with water and extracted with ethyl acetate (300 mL×2), dried (Na2SO4), and the solvent evaporated under vacuum. The crude product was purified by CC using EtOAc/PE (3:7) as eluent to get 1-(2,3-dichlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-5-amine (17.02 g, 39.65%, yellow solid; TLC system: EtOAc/PE (1:1) Rf: 0.6).

Workup

  1. temperaturerefluxed for 3 h
  2. customEthanol was evaporated
  3. additionthe residue diluted with water
  4. extractionextracted with ethyl acetate (300 mL×2)
  5. dry with materialdried (Na2SO4)
  6. customthe solvent evaporated under vacuum
  7. customThe crude product was purified by CC

Sources & evidence

ORD record
ord-a7434c93560e4adf85c52bd09f5553e4
Source dataset
uspto-grants-2015_02
Patent number
US08946204B2

Reaction notes

Loading…