4-Methoxyphenylhydrazine hydrochloride → 3-isopropyl-1-(4-methoxyphenyl)-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 (514 mg, 4.5 mmol) prepared as described in Example 122A Step 1, in anhydrous EtOH (15 ml) was added (4-methoxyphenyl)hydrazine hydrochloride (524 mg, 3.0 mmol) and the reaction mixture was heated at 80° C. overnight. The residue was purified by silica gel chromatography (DCM/EtOAc 1:1) to afford 3-isopropyl-1-(4-methoxyphenyl)-1H-pyrazol-5-amine (333 mg, 48%) as a solid. 1H NMR (300 MHz, CDCl3) δ 1.26 (d, J=7 Hz, 6H), 2.92 (m, 1H), 3.66 (s, 2H), 3.83 (s, 3H), 5.46 (s, 1H), 6.96 (d, J=9 Hz, 2H), 7.44 (d, J=9 Hz, 2H); LC-MS (ESI) m/z 232 (M+H)+.

Provenance & Evidence