(4-Fluorophenyl)hydrazine → 3-tert-butyl-1-(4-fluorophenyl)-1H-pyrazol-5-amine

Participants

Reaction Steps

The title compound is prepared according to a published literature procedure (see J. Med. Chem. 2002, 45, 2994-3008.): 4.17 g (32.3 mMol) of pivaloylacetonitrile are added to a solution of 4.20 g (32.3 mMol) 4-fluoro-phenylhydrazine in 150 ml of toluene at rt, and the resulting yellow solution is heated to and kept under reflux for 12 h. After completion, the reaction mixture is concentrated, and the resulting crude product is purified by flash chromatography (SiO2, 100% CH2Cl2) to give the title compound as a yellow solid: 1HNMR (CDCl3) δ ppm 7.59 (d, 2H), 7.10 (d, 2H), 5.58 (s, 1H), 3.62 (brs, H2N), 1.32 (s, 9H).

Provenance & Evidence