反应详情

A solution of 1-(4-(3-methoxy-4-nitrophenyl)piperazin-1-yl)ethanone (20a) in 10 mL of EtOH was hydrogenated with a balloon filled with hydrogen in the presence of palladium (10 wt. % on activated carbon, 0.61 g, 0.57 mmol) for 18 h at RT. It was filtered through a pad of Celite and rinsed with EtOAc (2×20 mL). The filtrate was concentrated. The brown residue was triturated with 10 mL of hexanes. The liquid was decanted. The solid was dried in a vacuum oven at 40° C. for 1 h to give 1-(4-(4-amino-3-methoxyphenyl)piperazin-1-yl)ethanone (20b; 1.42 g, 5.70 mmol, 99% yield) as a brown solid. Crude material used in the next step. 1H NMR (400 MHz, DMSO-d6) δ ppm 6.54 (2H, m), 6.32 (1H, dd, J=8.3, 2.4 Hz), 4.63 (2H, br.), 3.76 (3H, s), 3.54 (4H, m), 2.95 (2H, m), 2.89 (2H, m), 2.02 (3H, s). m/z (ESI, +ve ion) 250.1 (M+H)+.

1. filtrationIt was filtered through a pad of Celite
2. washrinsed with EtOAc (2×20 mL)
3. concentrationThe filtrate was concentrated
4. customThe brown residue was triturated with 10 mL of hexanes
5. customThe liquid was decanted
6. customThe solid was dried in a vacuum oven at 40° C. for 1 h