Hydrazine hydrate (1:1) → 6-fluoro-1H-indazol-3-amine

HRID 250023Notes

Reaction equation

HRID 250023 reaction equation
F[C:2]1[CH:9]=[C:8]([F:10])[CH:7]=[CH:6][C:3]=1[C:4]#[N:5].O.[NH2:12][NH2:13]>>[F:10][C:8]1[CH:9]=[C:2]2[C:3]([C:4]([NH2:5])=[N:12][NH:13]2)=[CH:6][CH:7]=1

Participants

3

Reactant 2

HCID 24654Hydrazine hydrate (1:1)HCID 775452,4-Difluorobenzonitrile

Product 1

HCID 219392676-fluoro-1H-indazol-3-amineYield 38%

Procedure

To 2,4-difluorobenzonitrile (1.21 g, 8.70 mmol) was added hydrazine monohydrate (8.46 mL, 174 mmol). The mixture was heated to reflux for 5 hours and then poured onto ice. The solution was extracted with ethyl acetate, dried with magnesium sulfate, filtered and concentrated. The residue was purified by column chromatography (25-100% ethyl acetate/hexane) to afford 6-fluoro-1H-indazol-3-amine (0.5 g, 3.3 mmol, 38% yield) as light yellow powder. 1H NMR (500 MHz, DMSO-D6) δ ppm 11.42 (s, 1 H), 7.70 (dd, J=8.55, 5.49 Hz, 1 H), 6.97 (dd, J=10.07, 1.83 Hz, 1 H), 6.72-6.79 (m, 1 H), 5.40 (s, 2 H). MS (LC/MS) R.T.=0.61; [M+H]+=152.11.

Workup

  1. temperatureThe mixture was heated
  2. temperatureto reflux for 5 hours
  3. additionpoured onto ice
  4. extractionThe solution was extracted with ethyl acetate
  5. dry with materialdried with magnesium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customThe residue was purified by column chromatography (25-100% ethyl acetate/hexane)

Sources & evidence

ORD record
ord-66c4f5a18d8e4e589f065d39e7ada3bb
Source dataset
uspto-grants-2011_01
Patent number
US07863291B2

Reaction notes

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