Sulfuric Acid → 5-Bromo-benzo[2,1,3]thiadiazole

HRID 1819975Notes

Reaction equation

HRID 1819975 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([NH2:8])=[C:4]([NH2:9])[CH:3]=1.[S:10](Cl)(Cl)=O.S(=O)(=O)(O)O>>[Br:1][C:2]1[CH:7]=[CH:6][C:5]2=[N:8][S:10][N:9]=[C:4]2[CH:3]=1

Participants

4

Reactant 3

HCID 1118Sulfuric AcidHCID 24386Thionyl ChlorideHCID 3235934-Bromobenzene-1,2-diamine

Product 1

HCID 27762955-Bromo-benzo[2,1,3]thiadiazole

Procedure

A mixture was prepared by mixing 4.0 g (21 mmol) of 4-bromo-o-phenylenediamine, 14 mL of thionyl chloride and 0.62 mL of concentrated sulfuric acid and was refluxed for one hour. This mixture was cooled and then poured onto ice, and a resulting precipitate was filtered and collected. This precipitate was washed with water till the waste water became neutral and then thoroughly dried to yield 4.5 g of 5-bromo-2,1,3-benzothiadiazole as a crude product (melting point, 48 to 50° C.; yield, 96.5%). This crude product was vacuum-distilled to yield a pure product of 5-bromo-2,1,3-benzothiadiazole (melting point, 50° C.; yield, 86%).

Workup

  1. customA mixture was prepared
  2. temperaturewas refluxed for one hour
  3. temperatureThis mixture was cooled
  4. additionpoured onto ice
  5. filtrationa resulting precipitate was filtered
  6. customcollected
  7. washThis precipitate was washed with water till the waste water
  8. customthoroughly dried

Sources & evidence

ORD record
ord-6cfe779b6938441ab4cce23a72fcf8f8
Source dataset
uspto-grants-2009_10
Patent number
US07601873B2

Reaction notes

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