Hydrochloric Acid → 4-Nitro-1,2-dihydro-3H-indazol-3-one

HRID 2112076Notes

Reaction equation

HRID 2112076 reaction equation
[NH2:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]([N+:11]([O-:13])=[O:12])[C:3]=1[C:4](O)=[O:5].Cl.[N:15]([O-])=O.[Na+].S(=O)=O>O>[N+:11]([C:7]1[CH:8]=[CH:9][CH:10]=[C:2]2[C:3]=1[C:4](=[O:5])[NH:15][NH:1]2)([O-:13])=[O:12]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 1119Sulfur Dioxide2×HCID 957952-Amino-6-nitro-benzoic acidHCID 23668193Sodium Nitrite

Product 1

HCID 247281924-Nitro-1,2-dihydro-3H-indazol-3-one

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

5 g (27.5 mmol) 2-amino-6-nitro-benzoic acid are combined with 22.2 ml (225.3 mmol) concentrated HCl and 45 ml (30.0 mmol) 5% aqueous sodium nitrite solution and stirred for 1 h at ambient temperature. Then the suspension is diluted with 150 ml dist. H2O and added dropwise to 350 ml destilliertes water which has been saturated with sulphur dioxide. Sulphur dioxide is piped through the reaction mixture for a further 30 min. Then the reaction mixture is refluxed for 30 min and then left to cool slowly to 20° C. The resulting precipitate is filtered off.

Workup

  1. additionThen the suspension is diluted with 150 ml dist
  2. temperatureThen the reaction mixture is refluxed for 30 min
  3. waitleft
  4. temperatureto cool slowly to 20° C
  5. filtrationThe resulting precipitate is filtered off

Sources & evidence

ORD record
ord-d327fcefa8d440e79300a236590609fb
Source dataset
uspto-grants-2009_04
Patent number
US07521457B2

Reaction notes

Loading…