1,4-Dimethyl-3-(4-nitrophenyl)piperazin-2-one → 3-(4-Aminophenyl)-1,4-dimethylpiperazin-2-one

Participants

Reaction Steps

A 50-mL single-neck round-bottomed flask equipped with a magnetic stirrer was purged with nitrogen and charged with 1j (200 mg, 0.80 mmol), ethanol (5 mL) and 10% palladium on carbon (50% wet, 4 mg dry weight). The reaction flask was purged with hydrogen gas and the reaction mixture stirred under a balloon pressure of hydrogen for 2 h. After this time the flask was purged with nitrogen. The catalyst was removed by filtration through a pad of Celite 521 and the filter cake washed with ethanol (10 mL). The filtrate was concentrated under reduced pressure to afford a 94% yield of 1k (166 mg) as a colorless oil: 1H NMR (500 MHz, DMSO-d6) δ 6.89 (d, 2H, J=8.5 Hz), 6.47 (d, 2H, J=8.5 Hz), 4.94 (s, 2H), 3.53 (td, 1H, J=12.0, 4.0 Hz), 3.44 (m, 1H), 3.21 (dt, 1H, J=12.0, 4.0 Hz), 2.92 (dt, 1H, J=12.0, 4.0 Hz), 2.82 (s, 3H), 2.02 (s, 3H); MS (ESI+) m/z 220 (M+H).

Provenance & Evidence