1,5,6,7-tetrahydro-4H-indazol-4-one → HCID 59252674, compound

HRID 2366486Notes

Reaction equation

HRID 2366486 reaction equation
[Br-:1].[Br-].[Br-].[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1.[NH:22]1[C:30]2[CH2:29][CH2:28][CH2:27][C:26](=[O:31])[C:25]=2[CH:24]=[N:23]1>C(O)(=O)C>[Br:1][CH:27]1[CH2:28][CH2:29][C:30]2[NH:22][N:23]=[CH:24][C:25]=2[C:26]1=[O:31]

Participants

4

Reactant 2

HCID 101712471,5,6,7-tetrahydro-4H-indazol-4-oneHCID 21124087Pyridiniumtribromide

Product 1

HCID 59252674HCID 59252674, compoundYield 90.7%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

According to Scheme 1 Step 3: Pyridinium tribromide (25.7 mmol, 8.22 g) was added to a solution of 6,7-dihydro-1H-indazol-4(5H)-one (25.7 mmol, 3.50 g) in acetic acid (60 mL) and the reaction mixture was stirred under reflux for 2 hours. After evaporation of the solvent, the crude residue was partitioned between DCM and a saturated solution of Na2S2O3. The organic phase was washed with a saturated solution of Na2CO3 and with water, was dried over Na2SO4 and concentrated to yield 5-bromo-6,7-dihydro-1H-indazol-4(5H)-one (23.3 mmol, 5.00 g, 90%).

Workup

  1. temperatureunder reflux for 2 hours
  2. customAfter evaporation of the solvent
  3. customthe crude residue was partitioned between DCM
  4. washThe organic phase was washed with a saturated solution of Na2CO3 and with water
  5. dry with materialwas dried over Na2SO4
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-eef6037af2394052abfcf903265b8b66
Source dataset
uspto-grants-2014_04
Patent number
US08697744B2

Reaction notes

Loading…