Phenylhydrazine hydrochloride → 3-(1-Methylethyl)-1-phenyl-1H-pyrazol-5-amine

Participants

Reaction Conditions

Reaction Steps

Using the procedure described in Example 308A Step 1, to a solution of 4-methyl-3-oxopentanenitrile (303 mg, 2.7 mmol) prepared as described in Example 122A Step 1, in anhydrous EtOH (6 ml) was added phenylhydrazine hydrochloride (473 mg, 3.3 mmol) and the reaction mixture was heated at 65° C. overnight. The residue was purified by silica gel chromatography (hexane/ethyl acetate 2-50%) to afford 3-isopropyl-1-phenyl-1H-pyrazol-5-amine (423 mg, 77%) as a solid. 1H NMR (300 MHz, CDCl3) δ 1.22 (d, J=6 Hz, 6H), 3.86 (brs, 2H), 5.35 (s, 1H), 7.21-7.49 (m, 5H); LC-MS (ESI) m/z 202 (M+H)+.

Provenance & Evidence