Pentane → 3-(tert-Butyl)-1-(4-methoxyphenyl)-1H-pyrazol-5-amine

Participants

Reaction Steps

4,4-Dimethyl-3-oxo-pentanenitrile (14.28 g, 114 mmol) and 4-methoxyphenyl hydrazine (19.89 g, 114 mmol) were dissolved in a mixture of absolute ethanol (170 mL) and glacial acetic acid (5.0 mL) then heated to reflux for 3 h, before allowing to standing overnight at RT. The resulting red/brown solid was filtered off, and the filtrate was then diluted with water (500 mL), and basified with 880 ammonia solution until the pH=5. This aqueous solution was extracted into diethyl ether (3×). The combined organics were dried (MgSO4) and evaporated in vacuo to a brown oil. Trituration (pentane) gave the title compound as a light purple/brown solid (23.07 g, 94.1 mmol, 82%). LCMS (method 1): Rt 2.87 min, m/z 246/247 [MH+].

Provenance & Evidence