Malononitrile → Benzothiazole, 2,2'-methylenebis-

HRID 1532944Notes

Reaction equation

HRID 1532944 reaction equation
[C:1](#[N:5])[CH2:2][C:3]#[N:4].N[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][C:8]=1[SH:13]>C(O)C>[S:13]1[C:8]2[CH:9]=[CH:10][CH:11]=[CH:12][C:7]=2[N:4]=[C:3]1[CH2:2][C:1]1[S:13][C:8]2[CH:9]=[CH:10][CH:11]=[CH:12][C:7]=2[N:5]=1

Participants

4

Reactant 2

HCID 8010MalononitrileHCID 87132-Aminothiophenol

Product 1

HCID 74755Benzothiazole, 2,2'-methylenebis-Yield 82%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To produce the above compound, in a two-neck 100 ml round bottom flask with a condenser and a stir bar, malononitrile (2.64 g, 40 mmol) was dissolved in absolute ethanol (40 ml). 2-amino thiophenol (10 g, 80 mmol) was slowly added to this solution under stirring. Under a nitrogen blanket, the reaction mixture was heated and refluxed for six hours. After cooling, the flask was refrigerated overnight. Pale green crystals of bis(2-benzothiazolyl) methane that formed were recovered following vacuum filtration, washing with hexane and drying (yield: 82%). 2.82 g (10 mmol) of the bis(2-benzothiazolyl) methane was dissolved in chloroform (50 ml) in an erlenmeyer flask. Hydrobromic acid (10 mmol) in glacial acetic acid was added dropwise with gentle stirring. A canary yellow precipitate formed within minutes, causing thickening of the reaction mixture. Stirring was continued for one hour at room temperature. A fine yellow powder was recovered, following filtration and washing with ether. The yield was quantitative and the bis(2-benzothiazolyl) methane monohydrobromide product was sufficiently pure to be used in the next step.

Workup

  1. customTo produce the above compound
  2. temperatureUnder a nitrogen blanket, the reaction mixture was heated
  3. temperaturerefluxed for six hours
  4. temperatureAfter cooling

Sources & evidence

ORD record
ord-90130bc5a97a4b51ad9fb9b99a19a44d
Source dataset
uspto-grants-2001_03
Patent number
US06207464B1

Reaction notes

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