2-Amino-6-Chloropyrazine → 2-Chloro-6-(3-[2,2,2-trifluoroethyl]thioureido)pyrazine

HRID 34819

Reaction equation

HRID 34819 reaction equation
[NH2:1][C:2]1[CH:7]=[N:6][CH:5]=[C:4]([Cl:8])[N:3]=1.[F:9][C:10]([F:16])([F:15])[CH2:11][N:12]=[C:13]=[S:14]>C(#N)C>[F:9][C:10]([F:16])([F:15])[CH2:11][NH:12][C:13](=[S:14])[NH:1][C:2]1[CH:7]=[N:6][CH:5]=[C:4]([Cl:8])[N:3]=1

Participants

4

Reactant 2

HCID 1184582-Amino-6-ChloropyrazineHCID 138837771,1,1-Trifluoro-2-isothiocyanatoethane2×

Product 1

HCID 544834192-Chloro-6-(3-[2,2,2-trifluoroethyl]thioureido)pyrazineYield 36.9%

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

A solution of 2-amino-6-chloropyrazine (1 g.) in warm acetonitrile (15 ml.) was cooled to room temperature. Trifluoroethylisothiocyanate (1.6 g.) was added and the mixture stirred overnight. Further trifluoroethylisothiocyanate (1.6 g.) was added, and the mixture warmed gently on a steam bath for 2 hours, then heated under reflux for 2 hours. The mixture was allowed to cool and evaporated to dryness to yield a brown solid. This was washed with water, 2N HCl solution, water again, and sucked dry. Recrystallisation from boiling toluene diluted with petroleum ether (b.p. 60°-80°) yielded colourless needles (0.77 g.) of 2-[3-(2,2,2-trifluoroethyl)thioureido]-6-chloropyrazine m.p. 170°-172°.

Workup

  1. temperaturethe mixture warmed gently on a steam bath for 2 hours
  2. temperatureheated
  3. temperatureunder reflux for 2 hours
  4. temperatureto cool
  5. customevaporated to dryness
  6. customto yield a brown solid
  7. washThis was washed with water, 2N HCl solution, water again
  8. customsucked dry
  9. customRecrystallisation
  10. additiondiluted with petroleum ether (b.p. 60°-80°)

Sources & evidence

ORD record
ord-5c2b8e3ec85846b6a051d3a4ba2184fb
Source dataset
uspto-grants-1988_08
Patent number
US04762932

Linked notes

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