Thiourea → 6-Methyl-4,5,6,7-tetrahydro-1,3-benzothiazol-2-amine

HRID 2059050Notes

Reaction equation

HRID 2059050 reaction equation
[NH2:1][C:2]([NH2:4])=[S:3].Br[CH:6]1[CH2:11][CH:10]([CH3:12])[CH2:9][CH2:8][C:7]1=O>C(O)C>[NH2:1][C:2]1[S:3][C:6]2[CH2:11][CH:10]([CH3:12])[CH2:9][CH2:8][C:7]=2[N:4]=1

Participants

4

Reactant 2

HCID 2723790ThioureaHCID 124904552-Bromo-4-methylcyclohexan-1-one

Product 1

HCID 3469226-Methyl-4,5,6,7-tetrahydro-1,3-benzothiazol-2-amine

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

Thiourea (22.3 g., 0.29 mole) was slurried in 275 ml. of ethanol. 2-Bromo-4-methylcyclohexanone was added and the mixture heated to reflux for 75 minutes. The reaction mixture was cooled to room temperature and the crude product recovered as the hydrobromide salt by filtration. The crude salt was dissolved in warm water, filtered and made basic with ammonium hydroxide to precipitate the free base as an oil, which crystallized on cooling. Purified 2-amino-4,5,6,7-tetrahydro-6-methylbenzthiazole (25.2 g., m.p. 98°-100° C.) was obtained by recrystallization from cyclohexane.

Workup

  1. temperaturethe mixture heated
  2. temperatureto reflux for 75 minutes
  3. filtrationthe crude product recovered as the hydrobromide salt by filtration
  4. dissolutionThe crude salt was dissolved in warm water
  5. filtrationfiltered
  6. customto precipitate the free base as an oil, which
  7. customcrystallized
  8. temperatureon cooling

Sources & evidence

ORD record
ord-6c21d931920e406a87f2ad2e4e7c0c6d
Source dataset
uspto-grants-1982_03
Patent number
US04321372

Reaction notes

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