6-FLUORO(1H)INDAZOLE

A mixture of 5-fluoro-2-methylaniline (3g, 0.024mo1), potassium acetate (2.8 g, 0.028 mol) and acetic anhydride (6.8 mL, 0.072mo1) in chloroform (30 mL) was heated at 40 °C for 0.5 h. At this temperature isoamylnitrate (3.8 mL, 0.028mo1) was added and stined at 80 °C for 12 h. After completion of reaction, solvent was removed under reduced pressure, the residue wasbasified with sodium carbonate solution and was extracted with ethyl acetate. The organic layer was washed with water followed by brine solution and concentrated under reduced pressure to obtain crude compound. The residue was purified by column chromatography over silica gel (30 percent EtOAc:Hexane) to give the pure compound which was stined with methanolic HC1 (60 mL) for 30 mm. The reaction mixture was concentrated under reduced pressure, basified withaqueous sodium carbonate solution and extracted with ethyl acetate. The organic layer was washed with water, brine and was dried over anhydrous Na2SO4 and concentrated under reduced pressure to obtain crude compound. The crude compound was purified by columnchromatography (n-hexanel EtOAc 7:3) to give the title compound (2.0 g, 62 percent) as a pale yellow solid.Synthesis of 6-fluoro-1H-indazole General procedure: The title compounds were obtained by modifying a method described by Lukin et al. [63]. To the properly substituted 2-fluorobenzaldehyde (5 g, 35 mmol) was added hydrazine hydrate (12.9 g, 258 mmol, 12.5 ml). After stirring for 12-48 h (TLC control) at reflux water (20 ml) was added and the resulting mixture was cooled to 5 °C. The precipitate was collected by vacuum filtration. The filtrate was extracted with dichloromethane and the residue after evaporation was combined with the precipitate.To a stined mixture of To a stirred mixture of NaNO3 (5100mg, 60mmol) was placed in a 500mL reaction flask.60 mL of concentrated sulfuric acid, General procedure: Route 1: Argon under the protection, Compound 2 (0.2 mmol) was dissolved in 2 mL of methanol, Add magnesium powder, Room temperature reaction for 3 hours, The organic phase was washed with saturated ammonium chloride solution and brine, dried over anhydrous MgSO4, the solvent was evaporated under reduced pressure, and the column was evaporated on the column.The compound 3 was isolated by chromatography.

Molecular Weight:136.13
XLogP3:2.3
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Exact Mass:136.04367633
Monoisotopic Mass:136.04367633
Topological Polar Surface Area:28.7
Heavy Atom Count:10
Complexity:129
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes