Hydrochloric Acid → 1-(3-(trifluoromethyl)phenyl)-1H-pyrazole

HRID 2198760Notes

Reaction equation

HRID 2198760 reaction equation
[F:1][C:2]([F:12])([F:11])[C:3]1[CH:4]=[C:5]([NH:9][NH2:10])[CH:6]=[CH:7][CH:8]=1.O.Cl.C(O[CH:18](OCC)[CH2:19][CH:20](OCC)OCC)C>C(O)C>[F:1][C:2]([F:11])([F:12])[C:3]1[CH:4]=[C:5]([N:9]2[CH:20]=[CH:19][CH:18]=[N:10]2)[CH:6]=[CH:7][CH:8]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 962WaterHCID 671471,1,3,3-TetraethoxypropaneHCID 98650(3-(Trifluoromethyl)phenyl)hydrazine

Product 1

HCID 130663261-(3-(trifluoromethyl)phenyl)-1H-pyrazoleYield 80%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

Into a 500 ml., 2-neck flask, fitted with a condenser and a magnetic stirrer, is successively added 35.2 g. (0.2 M.) of m-trifluoromethylphenyl hydrazine, 15 ml. of water, 20 ml. of 100% ethanol, 16.5 ml. of concentrated hydrochloric acid (slowly) and 44.0 g. (0.2 M.) of 1,1,3,3-tetraethoxypropane. The reaction mixture is then heated slowly to between 80° C. and 90° C., and after maintaining the mixture at this temperature range for a period of between 2 and 3 hours, the reaction mixture is cooled, quenched on ice water, extracted with ethylacetate and washed several times with water. After drying the organic solution over sodium sulfate, the solvent is evaporated on a rotary evaporator to obtain a very dark liquid which is then distilled at 70° to 80° C. and a pressure of about 100 microns to yield a light yellow oil (Yield: 80%).

Workup

  1. custom, 2-neck flask, fitted with a condenser and a magnetic stirrer
  2. temperatureThe reaction mixture is then heated slowly to between 80° C. and 90° C.
  3. temperatureafter maintaining the mixture at this temperature range for a period of between 2 and 3 hours
  4. temperaturethe reaction mixture is cooled
  5. customquenched on ice water
  6. extractionextracted with ethylacetate
  7. washwashed several times with water
  8. dry with materialAfter drying the organic solution over sodium sulfate
  9. customthe solvent is evaporated on a rotary evaporator
  10. customto obtain a very dark liquid which
  11. distillationis then distilled at 70° to 80° C.

Sources & evidence

ORD record
ord-89e72e5c99df4859a7416ab560b29bec
Source dataset
uspto-grants-1982_11
Patent number
US04359474

Reaction notes

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