General procedure for the synthesis of 3-aminopiperidine-2,6-dione hydrochloride from benzyl (2,6-dioxopiperidin-3-yl)carbamate: Benzyl (2,6-dioxopiperidin-3-yl)carbamate (4.00 g, 15.0 mmol) was dissolved in methanol (200 mL) and 2N HCl solution (15 mL) was added. Subsequently, 5% Pd-C catalyst (100 mg) was added and the hydrogenation reaction was carried out at 60 psi hydrogen pressure for 4 hours. Upon completion of the reaction, the catalyst was removed by filtration and the filtrate was concentrated to dryness to afford 3-aminopiperidine-2,6-dione hydrochloride as a white solid (2.61 g, 100% yield) with a melting point of 245 °C (decomposition, ignition temperature 235 °C).1H NMR (400 MHz, DMSO-D6) δ ppm: 11.22 (br s, 1H), 8.68 (br s, 3H), 4.20 (dd, J = 13.0, 5.3 Hz, 1H), 2.77-2.65 (m, 1H), 2.64-2.56 (m, 1H), 2.27-2.19 (m, 1H), 2.09-1.97 (m, 1H).
