2-Bromo-4-chloro-6-methylbenzenamine → 7-Bromo-5-chloro-1H-indazole

HRID 855240Notes

Reaction equation

HRID 855240 reaction equation
[Br:1][C:2]1[CH:8]=[C:7]([Cl:9])[CH:6]=[C:5]([CH3:10])[C:3]=1[NH2:4].[N:11]([O-])=O.[Na+]>C(O)(=O)C.O>[Br:1][C:2]1[CH:8]=[C:7]([Cl:9])[CH:6]=[C:5]2[C:3]=1[NH:4][N:11]=[CH:10]2

Participants

5

Reactant 2

HCID 205437542-Bromo-4-chloro-6-methylbenzenamineHCID 23668193Sodium Nitrite

Product 1

HCID 269676217-Bromo-5-chloro-1H-indazoleYield 88.1%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 962WaterSolvent

Procedure

2.20 g (10 mmol) of 2-bromo-4-chloro-6-methyl aniline were dissolved in 125 ml acetic acid. 0.69 g (10 mmol) of sodium nitrite dissolved in 2 ml water were added dropwise. The reaction mixture was stirred at rt for 4 h. Acetic acid was evaporated and the residue dissolved in EtOAc. The organic layer was washed with water, dried over sodium sulfate, filtered and the solvent was evaporated. The residue was several times evaporated with heptane to yield 2.04 g (88%) of 7-bromo-5-chloro-1H-indazol as a light brown solid. 1H NMR (DMSO-d6, 300 MHz): δ 8.23 (s, 1H), 7.91 (s, 1H), 7.67 (s, 1H).

Workup

  1. additionwere added dropwise
  2. customAcetic acid was evaporated
  3. dissolutionthe residue dissolved in EtOAc
  4. washThe organic layer was washed with water
  5. dry with materialdried over sodium sulfate
  6. filtrationfiltered
  7. customthe solvent was evaporated
  8. customevaporated with heptane

Sources & evidence

ORD record
ord-f841688c9249413cbd278adfafd336de
Source dataset
uspto-grants-2007_08
Patent number
US07259183B2

Reaction notes

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