Hydrazine hydrate (1:1) → 3-Amino-5-nitroindazole

Participants

Reaction Steps

Hydrazine monohydrate (17.5 mL, 362 mmol) was added to a hot (50° C.) solution of 2-fluoro-5-nitrobenzonitrile (30 g, 181 mmol) in EtOH (500 mL). The mixture was heated at reflux for 4 hours then allowed to cool to room temperature, whereupon the product precipitated from solution. The filtrate was concentrated and the residue partitioned between EtOAc and saturated ammonium chloride solution. The organic phase was separated, dried over magnesium sulfate and concentrated to obtain further product. The combined product (32.2 g, quant.) was taken on to the following step without further purification.

Provenance & Evidence