Hydrochloric Acid → 3-(Trifluoromethyl)pyrazole

HRID 1470774Notes

Reaction equation

HRID 1470774 reaction equation
[F:1][C:2]([F:10])([F:9])[C:3](=O)[CH:4]=[CH:5]OC.Cl.O.[NH2:13][NH2:14].[OH-].[Na+]>O.C(O)C>[F:1][C:2]([F:10])([F:9])[C:3]1[CH:4]=[CH:5][NH:14][N:13]=1

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 24654Hydrazine hydrate (1:1)HCID 537273361,1,1-Trifluoro-4-methoxy-3-buten-2-one

Product 1

HCID 18070343-(Trifluoromethyl)pyrazoleYield 92%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 962WaterSolvent

Procedure

2.71 kg of 1,1,1-trifluoro-4-methoxy-but-3-en-2-on, 2.44 kg of ethanol and 3.10 kg of water were charged into a reaction vessel. 20 ml of concentrated hydrochloric acid and 0.80 kg of hydrazine hydrate were successively added and the mixture was heated to reflux for 4 h. The mixtures was allowed to cool and neutralized by addition of 10% aqueous NaOH to about pH 4-5. Then the mixture was evaporated. Toluene was added and the mixture was again evaporated to yield 2 kg of raw 3-trifluoromethyl-pyrazole with a purity of >85%.

Workup

  1. temperaturethe mixture was heated
  2. temperatureto reflux for 4 h
  3. temperatureto cool
  4. customThen the mixture was evaporated
  5. additionToluene was added
  6. customthe mixture was again evaporated

Sources & evidence

ORD record
ord-d4e4f84c05a14f7987a39cdb0a894bc8
Source dataset
uspto-grants-2015_04
Patent number
US09006485B2

Reaction notes

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