Hydrazine hydrate (1:1) → 3-amino-1H-indazole-6-carboxylic Acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-cyano-3-fluorobenzoic acid (500 mg, 3.0 mmol) in n-butanol (9 mL) was added hydrazine monohydrate (0.5 mL, 10 mmol). The reaction was heated to 110° C. overnight. The reaction was cooled to room temperature and the precipitate was collected by filtration. The solid was then dissolved in 1 N aqueous sodium hydroxide (2 mL) and extracted with ethyl acetate (2×). The aqueous layer was acidified to pH=4 with 1 N aqueous hydrochloric acid. The resulting precipitate was collected by filtration and dried under vacuum to provide the title compound (140 mg, 26%) as a red solid. +ESI (M+H) 178.2; 1H NMR (400 MHz, CD3OD, δ): 7.99-8.01 (m, 1H), 7.73 (dd, J=8.4, 0.8 Hz, 1H), 7.61 (dd, J=8.5, 1.3 Hz, 1H).

Provenance & Evidence