(2-PIPERIDIN-4-YL-ETHYL)-CARBAMIC ACID TERT-BUTYL ESTER

109573-05-9

165528-81-4

General procedure for the synthesis of 4-(2-Boc-aminoethyl)piperidine from tert-butyl N-[2-(pyridin-4-yl)ethyl]carbamate: tert-butyl N-[2-(pyridin-4-yl)ethyl]carbamate (26.9 g, 120.9 mmol) was dissolved in methanol (370 mL) and cooled to 0 °C. Aqueous 6N hydrochloric acid (20.2 mL, 120.9 mmol) was slowly added at 0 °C. Subsequently, platinum (IV) oxide (1.37 g, 6.05 mmol) was added to the reaction mixture at room temperature and the hydrogenation reaction was carried out under hydrogen (1000 psi) atmosphere for 24 hours. Upon completion of the reaction, the mixture was filtered through an Arbocel pad and the filter cake was washed sequentially with methanol (300 mL) and water (100 mL). The filtrate was concentrated under reduced pressure. The concentrated crude product was diluted with saturated aqueous sodium bicarbonate (150 mL) and extracted with dichloromethane (50 mL). The organic layer was washed with water (2 x 50 mL). The aqueous layers were combined, alkalized with 30% aqueous sodium hydroxide (30 mL) and then extracted with dichloromethane (8 x 200 mL). All organic layers were combined, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give 4-(2-Boc-aminoethyl)piperidine as a clear viscous oil (26.8 g, 97% yield). The product was characterized by 1H NMR (400 MHz, CDCl3) and LCMS: 1H NMR δ 1.17 (m, 2H), 1.41 (m, 10H), 1.68 (m, 2H), 2.58 (m, 2H), 3.09 (m, 6H), 4.53 (s, 1H); LCMS Rt = 1.73 min, MS m/z 229 [M + H ]+.