Acetic Acid → 4-(2,4,6-Trimethyl-phenyl)-2H-pyrazol-3-ylamine

Beteiligte Stoffe

Reaktionsschritte

A mixture of 3-oxo-2-(2,4,6-trimethyl-phenyl)-propionitrile (2.300 g, 12.3 mmol), hydrazine hydrate (0.93 g) and glacial acetic acid (1.55 ml) in 20 ml benzene was heated at reflux for 4.5 hours. Reaction mixture was cooled to room temperature and 50 ml of 18.5% HCl in water was added. The benzene layer was separated and reextracted with 18.5% HCl. The aqueous layer were combined and neutralized with ammonium hydroxide and stirred at rt. overnight. Precipitate formed and was filtered to yield the title compound (0.256 g) as a yellow solid. The benzene layer was concentrated and purified through silica gel column using 5% methanol in chloroform as eluent to give an additional 1.450 g of the title compound; 1H NMR (CDCl3) ä 7.24(s, 1H), 6.95(s, 2H), 4.75(brs, 2H), 2.32(s, 3H), 2.13(s, 6H) ppm.

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