Benzyl Bromide → 1-Benzyl-5-nitro-1H-indazole

HRID 1292965

Reaction equation

HRID 1292965 reaction equation
[N+:1]([C:4]1[CH:5]=[C:6]2[C:10](=[CH:11][CH:12]=1)[NH:9][N:8]=[CH:7]2)([O-:3])=[O:2].C(=O)([O-])[O-].[K+].[K+].[CH2:19](Br)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1>C(#N)C>[CH2:19]([N:9]1[C:10]2[C:6](=[CH:5][C:4]([N+:1]([O-:3])=[O:2])=[CH:12][CH:11]=2)[CH:7]=[N:8]1)[C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1

Participants

5

Reactant 3

HCID 7498Benzyl BromideHCID 11430Potassium CarbonateHCID 215015-Nitroindazole

Product 1

HCID 219520821-Benzyl-5-nitro-1H-indazoleYield 45.1%

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Conditions

Temperature
70 °C

Procedure

To a solution of 5-nitroindazole (10.0 g, 61.3 mmol) in acetonitrile (100 mL) was added potassium carbonate (16.9 g, 122.6 mmol) and benzyl bromide (13.6 g, 79.7 mmol). The resulting yellow reaction mixture was heated with stirring at 70° C. overnight. Upon cooling down, the solid was filtered off and washed with methylene chloride. The filtrate was concentrated to dryness and the resulting residue was purified by flash chromatography eluting with 17–25% ethyl acetate in hexanes (v/v) yielding 7.0 g (44%) of the corresponding 1-Benzyl-5-nitro-1H-indazole as a yellow solid.

Workup

  1. temperatureThe resulting yellow reaction mixture was heated
  2. temperatureUpon cooling down
  3. filtrationthe solid was filtered off
  4. washwashed with methylene chloride
  5. concentrationThe filtrate was concentrated to dryness
  6. customthe resulting residue was purified by flash chromatography
  7. washeluting with 17–25% ethyl acetate in hexanes (v/v)

Sources & evidence

ORD record
ord-1a4d388626f84811aaef5791b5b36270
Source dataset
uspto-grants-2007_07
Patent number
US07238701B2

Linked notes

Loading…