5-Nitroindazole → 3-Chloro-5-nitro-1H-indazole

HRID 1823913Notes

Reaction equation

HRID 1823913 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].[Cl:13]N1C(=O)CCC1=O>CC(O)=O>[Cl:13][C:7]1[C:6]2[C:10](=[CH:11][CH:12]=[C:4]([N+:1]([O-:3])=[O:2])[CH:5]=2)[NH:9][N:8]=1

Participants

4

Reactant 2

HCID 215015-NitroindazoleHCID 31398Chlorosuccinimide

Product 1

HCID 1785264933-Chloro-5-nitro-1H-indazoleYield 43.4%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Conditions

Temperature
50 °C

Procedure

5-Nitroindazole (5 g, 30.7 mmol) was suspended in glacial AcOH (150 mL) and the mixture heated to 50° C. N-Chlorosuccinimide (4.9 g, 36.8 mmol) was added and the mixture heated at relux (solution forms) for 1 hour. The reaction mixture was concentrated and partitioned between EtOAc and brine. The organic phase was washed with saturated sodium bicarbonate, dried over sodium sulfate and concentrated to a yellow solid. Recrystallisation from EtOH provided the title compound as a pale yellow solid (2.63 g, 43%); 1H NMR (400 MHz, DMSO) δ 7.73 (1H, d), 8.21 (1H, dd), 8.51 (1H, d), 13.97 (1H, brs); MS (ES−) m/e=196.

Workup

  1. temperaturethe mixture heated at relux (solution forms) for 1 hour
  2. concentrationThe reaction mixture was concentrated
  3. custompartitioned between EtOAc and brine
  4. washThe organic phase was washed with saturated sodium bicarbonate
  5. dry with materialdried over sodium sulfate
  6. concentrationconcentrated to a yellow solid
  7. customRecrystallisation from EtOH

Sources & evidence

ORD record
ord-6688dc0cc26c46b290b0df9783ac40e3
Source dataset
uspto-grants-2006_05
Patent number
US07041687B2

Reaction notes

Loading…