Methanol → Methyl 5-bromo-1H-indazole-3-carboxylate

HRID 1507112Notes

Reaction equation

HRID 1507112 reaction equation
S(=O)(=O)(O)O.[Br:6][C:7]1[CH:8]=[C:9]2[C:13](=[CH:14][CH:15]=1)[NH:12][N:11]=[C:10]2[C:16]([OH:18])=[O:17].[CH3:19]O>>[Br:6][C:7]1[CH:8]=[C:9]2[C:13](=[CH:14][CH:15]=1)[NH:12][N:11]=[C:10]2[C:16]([O:18][CH3:19])=[O:17]

Participants

4

Reactant 3

HCID 887MethanolHCID 1118Sulfuric AcidHCID 71573585-bromo-1H-indazole-3-carboxylic Acid

Product 1

HCID 12689298Methyl 5-bromo-1H-indazole-3-carboxylateYield 98%

Procedure

Concentrated sulfuric acid (1 mL) was added to a suspension of 5-bromo-1H-indazole-3-carboxylic acid (CXV) (1.30 g, 5.39 mmol) in dry MeOH (50 mL) and heated to reflux for 4 h under argon. The solution was cooled to room temperature and the MeOH was evaporated under vacuum. The residue was dissolved in EtOAc and washed with water. The organic phase was dried over Na2SO4, filtered and concentrated to afford methyl 5-bromo-1H-indazole-3-carboxylate (CXVI) as a white solid (1.35 g, 5.29 mmol, 98% yield). 1H NMR (DMSO-d6) δ ppm 14.13 (s, 1H), 8.21 (d, J=1.6 Hz, 1H), 7.67 (d, J=7.2 Hz, 1H), 7.59 (dd, J=7.2, 1.2 Hz, 1H), 3.92 (s, 3H); ESIMS found for C9H7BrN2O2 m/z 256.0 (M+H).

Workup

  1. temperatureheated
  2. temperatureto reflux for 4 h under argon
  3. customthe MeOH was evaporated under vacuum
  4. dissolutionThe residue was dissolved in EtOAc
  5. washwashed with water
  6. dry with materialThe organic phase was dried over Na2SO4
  7. filtrationfiltered
  8. concentrationconcentrated

Sources & evidence

ORD record
ord-d712c32b6fbc4ee7a78d44a1bc99e950
Source dataset
uspto-grants-2015_12
Patent number
US09221793B2

Reaction notes

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