Methane → 4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine

HRID 1457613Notes

Reaction equation

HRID 1457613 reaction equation
OCC[N+](C)(C)C.[F:8][C:9]([F:19])([F:18])[C:10]1[CH:11]=[C:12]([NH:16][NH2:17])[CH:13]=[CH:14][CH:15]=1.[C:20](#[N:23])[CH:21]=[CH2:22].Cl.C.[OH-].[Na+]>>[F:8][C:9]([F:18])([F:19])[C:10]1[CH:11]=[C:12]([N:16]2[CH2:22][CH2:21][C:20]([NH2:23])=[N:17]2)[CH:13]=[CH:14][CH:15]=1

Participants

7

Reactant 6

HCID 297MethaneHCID 305CholineHCID 313Hydrochloric AcidHCID 7855AcrylonitrileHCID 14798Sodium HydroxideHCID 98650(3-(Trifluoromethyl)phenyl)hydrazine

Product 1

HCID 477954,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amineYield 66.4%

Conditions

Temperature
95 °C

Procedure

Under ice-cooling, 10 drops of a 50% choline solution was added to a mixture of 20.0 g of 3-(trifluoromethyl)phenylhydrazine and 6.63 g of acrylonitrile, and the mixture was heated at 95° C. for one hour. After allowed to stand for cooling, 22 ml of 1N hydrochloric acid was added and the mixture was stirred at 95° C. for 10 minutes. After subjecting the mixture to hot activated charcoal treatment, the mixture was adjusted to an alkaline pH with a 10% aqueous sodium hydroxide solution under ice-cooling. Precipitated crystals were collected by filtration and washed, and recrystallized from a mixed solution of hexane and ethyl acetate to give 17.27 g of 1-[3-(trifluoromethyl)phenyl]-3-amino-2-pyrazoline (yield: 66%, melting point: 104°-107° C.).

Workup

  1. temperatureUnder ice-cooling
  2. temperaturefor cooling
  3. temperaturecooling
  4. customPrecipitated crystals
  5. filtrationwere collected by filtration
  6. washwashed
  7. customrecrystallized from a mixed solution of hexane and ethyl acetate

Sources & evidence

ORD record
ord-297d7e28965149e187a08cb19e173f2e
Source dataset
uspto-grants-1998_12
Patent number
US05849732

Reaction notes

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