309956-78-3

485820-12-0

309956-78-3

General procedure for the synthesis of (R)-3-Boc-aminopiperidine from benzyl (R)-3-((tert-butoxycarbonyl)amino)piperidine-1-carboxylate: 46.8 g of benzyl (R)-3-((tert-butoxycarbonyl)amino)piperidine-1-carboxylate (Compound IV), 2.3 g of 10% wet palladium-carbon (50% water) and 320 mL of methanol were added to an autoclave. The reaction system was replaced with nitrogen 3 to 4 times and the reaction temperature was raised to 35 to 40 °C under hydrogen pressure of 0.3 to 0.4 MPa and maintained for 2 hours. The progress of the reaction was monitored by HPLC until complete conversion of the feedstock. Upon completion of the reaction, the catalyst was removed by filtration and the filtrate was concentrated to be free of fractions. To the concentrate, 23 mL of dichloromethane and 46 mL of petroleum ether were added and the temperature was raised to 35 to 40 °C. At this temperature, 325 mL of petroleum ether was slowly added and held for 1 hour. The reaction mixture was then slowly cooled to -5~0°C and the solid product was collected by filtration. The solid was dried at 40~45°C to give 26.7 g of white solid (R)-3-Boc-aminopiperidine in 95.4% yield.