111669-25-1

Grey to purple powder

Tert-butyl 4-(3-nitropyridin-2-yl)piperazine-1-carboxylate (350 mg, 1.14 mmol) was used as a raw material and mixed with Pd/C (60.4 mg, 10% w/w, 0.0568 mmol) and methanol (6 mL). The hydrogenation reaction was carried out at room temperature using a hydrogen balloon to provide a hydrogen atmosphere. The reaction mixture was stirred for 2 h and then filtered through diatomaceous earth to remove the catalyst. The filtrate was concentrated under reduced pressure and purified by silica gel column chromatography (eluent ratio hexane/EtOAc/CH2Cl2 = 1:1:1) to afford the target product tert-butyl 4-(3-aminopyridin-2-yl)piperazine-1-carboxylate (246 mg, 78% yield) as a white powder. Mass spectrometry (EI) analysis resulted in a molecular ion peak (MH+) of 279.2 for C14H22N4O2.

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