Hydrazine hydrate (1:1) → HCID 178434225, compound

HRID 1880367Notes

Reaction equation

HRID 1880367 reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5](F)=[C:6]([C:8](=O)[CH3:9])[CH:7]=1.O.[NH2:13][NH2:14]>>[Br:1][C:2]1[CH:7]=[C:6]2[C:5](=[CH:4][CH:3]=1)[NH:14][N:13]=[C:8]2[CH3:9]

Participants

3

Reactant 2

HCID 24654Hydrazine hydrate (1:1)HCID 226074761-(5-Bromo-2-fluorophenyl)ethanone

Product 1

HCID 178434225HCID 178434225, compoundYield 73%

Conditions

Temperature
130 °C

Procedure

A solution of 1-(5-bromo-2-fluoro-phenyl)-ethanone (10 g, 46 mmol) in hydrazine hydrate (80 mL) was heated at reflux (130° C.) for 20 hours. The reaction mixture was cooled to room temperature, excess hydrazine hydrate was removed and the crude residue was purified by column chromatography (60-120 mesh silica gel) using 10% ethyl acetate in pet-ether as eluents to obtain 5-bromo-3-methyl-1H-indazole (7.09 g, 73%) as a solid. 1H NMR (CDCl3): δ 10.2-10.6 (br, 1H), 7.8-7.9 (s, 1H), 7.4-7.5 (d, 1H), 7.2-7.4 (d, 1H), 2.5-2.7 (s, 3H).

Workup

  1. temperatureThe reaction mixture was cooled to room temperature
  2. customexcess hydrazine hydrate was removed
  3. customthe crude residue was purified by column chromatography (60-120 mesh silica gel)

Sources & evidence

ORD record
ord-305989f8ecd54748b1ad9bbfb0d5e88c
Source dataset
uspto-grants-2012_11
Patent number
US08318762B2

Reaction notes

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