Trifluoroacetic acid → 2,4-Dihydro-4-methyl-5-(trifluoromethyl)-3H-1,2,4-triazole-3-thione

HRID 1721058Notes

Reaction equation

HRID 1721058 reaction equation
[CH3:1][NH:2][C:3](=[S:6])[NH:4][NH2:5].[F:7][C:8]([F:13])([F:12])[C:9](O)=O>>[CH3:1][N:2]1[C:9]([C:8]([F:13])([F:12])[F:7])=[N:5][NH:4][C:3]1=[S:6]

Participants

3

Reactant 2

HCID 6422Trifluoroacetic acidHCID 2723853N-Methylhydrazinecarbothioamide

Product 1

HCID 12391662,4-Dihydro-4-methyl-5-(trifluoromethyl)-3H-1,2,4-triazole-3-thioneYield 95.5%

Procedure

257 g (2.44 mol) of 4-methyl-thiosemicarbazide are added to 1.2 liters of trifluoroacetic acid, and the mixture is refluxed for 16 hours. It is then concentrated under a water pump vacuum, the residue is triturated with diethyl ether/petroleum ether (5:100 by volume), and the product, which is obtained as crystals, is isolated by filtration. 444.5 g (95.5% of theory) of 4-methyl-5-trifluoromethyl-2,4-dihydro-3H-1,2,4-triazole-3-thione of melting point 115° C. are obtained.

Workup

  1. temperaturethe mixture is refluxed for 16 hours
  2. concentrationIt is then concentrated under a water pump vacuum
  3. customthe residue is triturated with diethyl ether/petroleum ether (5:100 by volume)
  4. customthe product, which is obtained as crystals
  5. customis isolated by filtration

Sources & evidence

ORD record
ord-532e7d7cb23b4d72b538824649a00a0b
Source dataset
uspto-grants-1996_04
Patent number
US05508420

Reaction notes

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