Water → 1H-Indazol-5-ol

HRID 1269711Notes

Reaction equation

HRID 1269711 reaction equation
B(Br)(Br)Br.C[O:6][C:7]1[CH:8]=[C:9]2[C:13](=[CH:14][CH:15]=1)[NH:12][N:11]=[CH:10]2.O>C(Cl)Cl>[NH:12]1[C:13]2[C:9](=[CH:8][C:7]([OH:6])=[CH:15][CH:14]=2)[CH:10]=[N:11]1

Participants

5

Reactant 3

HCID 962WaterHCID 25134Boron tribromideHCID 133468605-Methoxy-1H-indazole

Product 1

HCID 1014381H-Indazol-5-olYield 77.8%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

A methylene chloride solution of boron tribromide (18.5 ml, 18.5 mmol) was added to a solution of 5-methoxy-1H-indazole (1.24 g, 8.40 mmol) in methylene chloride (84 ml) at 0° C. and stirred at room temperature for 10 hours. Then, water was poured into the reaction solution in an ice-water bath, followed by extraction with ethyl acetate. The organic layer was washed with a saturated aqueous sodium hydrogencarbonate solution and then a saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to remove the solvent, and the resulting residue was purified by a silica gel column chromatography (eluent: chloroform/methanol=96/4) to obtain 1H-indazol-5-ol (877 mg, 71%).

Workup

  1. extractionfollowed by extraction with ethyl acetate
  2. washThe organic layer was washed with a saturated aqueous sodium hydrogencarbonate solution
  3. dry with materiala saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate
  4. distillationdistilled under reduced pressure
  5. customto remove the solvent
  6. customthe resulting residue was purified by a silica gel column chromatography (eluent: chloroform/methanol=96/4)

Sources & evidence

ORD record
ord-7e09fc36907d4979b86cb161c3a065ec
Source dataset
uspto-grants-2007_04
Patent number
US07199147B2

Reaction notes

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