Hydrazine Sulfate → 4-Bromopyridazine-3,6-diol

HRID 15168

Reaction equation

HRID 15168 reaction equation
S(O)(O)(=O)=O.[NH2:6][NH2:7].[Br:8][C:9]1[C:10](O[C:13](=[O:15])[CH:14]=1)=[O:11]>O>[Br:8][C:9]1[C:10](=[O:11])[NH:6][NH:7][C:13](=[O:15])[CH:14]=1

Participants

4

Reactant 2

HCID 24842Hydrazine Sulfate2×HCID 800273-Bromo-2,5-furandione2×

Product 1

HCID 2549424-Bromopyridazine-3,6-diolYield 151%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

Hydrazine sulphate salt (51 g) was suspended in water (250 ml), heated to reflux and bromomaleic anhydride (90.38 g) was added dropwise. The mixture was heated at reflux for 4 hours then cooled to room temperature. The reaction was repeated with 29 g hydrazine sulphate, 53 g bromomaleic anhydride and 130 ml water. The precipitates were collected by filtration, washed with water and acetone and dried as a combined batch in vacuo to afford 4-bromo-1,2-dihydro-3,6-pyridazinedione as a white solid (113 g).

Workup

  1. temperatureheated
  2. temperatureto reflux
  3. temperatureThe mixture was heated
  4. temperatureat reflux for 4 hours
  5. filtrationThe precipitates were collected by filtration
  6. washwashed with water and acetone
  7. customdried as a combined batch in vacuo

Sources & evidence

ORD record
ord-d45f37f166944474839658fa69d9d642
Source dataset
uspto-grants-2010_06
Patent number
US07732460B2

Linked notes

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