N-bromobutanimide → 3-bromo-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-ol

HRID 1253544Notes

Reaction equation

HRID 1253544 reaction equation
[CH3:1][N:2]1[CH:6]=[C:5]([C:7]2[CH:8]=[C:9]([OH:16])[C:10]3[N:11]([N:13]=[CH:14][CH:15]=3)[CH:12]=2)[CH:4]=[N:3]1.[Br:17]N1C(=O)CCC1=O>C(#N)C.ClCCl>[Br:17][C:15]1[CH:14]=[N:13][N:11]2[CH:12]=[C:7]([C:5]3[CH:4]=[N:3][N:2]([CH3:1])[CH:6]=3)[CH:8]=[C:9]([OH:16])[C:10]=12

Participants

5

Reactant 2

HCID 67184N-bromobutanimide2×HCID 67374373HCID 67374373, compound

Product 1

HCID 673753833-bromo-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-ol

Reagents, catalysts & solvents 2

HCID 6342AcetonitrileSolventHCID 6344DichloromethaneSolvent

Procedure

6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-ol (75.0 mg, 0.350 mmol) was suspended in acetonitrile (4 ml). N-bromosuccinimide (68.5 mg, 0.385 mmol) was added and the mixture was allowed to stir. After 30 minutes, additional N-bromosuccinimide (6.9 mg, 0.039 mmol) was added and the mixture was allowed to stir for 1 h. The reaction mixture was diluted in dichloromethane, washed with water and 1 N aqueous sodium hydroxide. The pH of the combined aqueous layers was adjusted to pH 7 with 6 N HCl, then the aqueous layers were extracted with ethyl acetate (2×) and the combined organic layers were dried over sodium sulfate, filtered and concentrated. The residue was purified by column chromatography on silica gel (methanol/dichloromethane gradient) to afford 3-bromo-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-ol.

Workup

  1. stirringto stir for 1 h
  2. washwashed with water and 1 N aqueous sodium hydroxide
  3. extractionthe aqueous layers were extracted with ethyl acetate (2×)
  4. dry with materialthe combined organic layers were dried over sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customThe residue was purified by column chromatography on silica gel (methanol/dichloromethane gradient)

Sources & evidence

ORD record
ord-abb1c16dc2764d20a09c82c29a8d982f
Source dataset
uspto-grants-2013_06
Patent number
US08455477B2

Reaction notes

Loading…