Under nitrogen protection, (S)-1-Boc-3-hydroxypiperidine (10.0 g, 49.7 mmol) and triethylamine (7.82 mL, 54.7 mmol) were dissolved in dichloromethane (60 mL) and cooled to 0 °C. Subsequently, methanesulfonyl chloride (4.23 mL, 54.7 mmol) was slowly added dropwise and the reaction mixture was stirred at this temperature for 1 hour. Upon completion of the reaction, the reaction solution was diluted with deionized water (60 mL) and filtered through a hydrophobic glass stock. The organic layer was concentrated under reduced pressure to afford tert-butyl (3S)-3-(methylsulfonyloxy)piperidine-1-carboxylate (13.9 g, 49.7 mmol, 100% yield) as a colorless solid. The product was characterized by 1H NMR (400 MHz, DMSO-d6): δ (ppm) 4.76-4.71 (m, 1H, CH), 3.69-3.66 (m, 1H), 3.65-3.60 (m, 1H), 3.49-3.43 (m, 1H), 3.37-3.31 (m, 1H), 3.07 (s, 3H, CH3) , 2.02-1.96 (m, 1H), 1.94-1.91 (m, 1H), 1.87-1.80 (m, 1H), 1.59-1.53 (m, 1H), 1.48-1.45 (m, 9H).
