864448-41-9

864448-40-8

864448-41-9

Tert-butyl 9-benzyl-3-oxa-7,9-diazabicyclo[3.3.1]nonane-7-carboxylate (100 mg, 0.3 mmol) was used as a starting material, which was dissolved in ethanol (150 mL) and 10% Pd/C (250 mg) was added. The hydrogenation reaction was carried out at room temperature and 1 atmospheric pressure for 1 hour. Upon completion of the reaction, the catalyst was removed by filtration and the filtrate was concentrated under reduced pressure. The resulting residue was purified by column chromatography (eluent: TBME/MeOH/NH3, 95/5/0.5 to 90/10/2) to afford tert-butyl 3-oxa-7,9-diazabicyclo[3.3.1]nonane-7-carboxylate as colorless crystals (53 mg, 74% yield).1H-NMR (400 MHz, DMSO-d6) δ (ppm) : 1.38 (s, 9H), 2.64 (bd, 1H), 3.03 (bd, 1H), 3.17 (bd, 1H), 3.71 (m, 4H), 3.92 (d, 1H), 3.99 (d, 1H), 6.67 (bs, 0.5H), 7.27 (bs, 0.5H).MS (m/z) ES+: 229.1 (MH+, 100).