Under stirring conditions, (S)-tert-butyl 2-((benzyloxy)methyl)morpholine-4-carboxylate (5.27 g, 17.2 mmol) was dissolved in 200 mL of ethanol, followed by the addition of 0.527 g of palladium/activated carbon catalyst and two drops of 1N hydrochloric acid. The reaction system was replaced three times with hydrogen and then reacted overnight at 70 °C under hydrogen atmosphere, and the reaction progress was monitored by thin layer chromatography (TLC) until the feedstock was completely consumed. Upon completion of the reaction, the reaction was quenched with 100 mL of saturated sodium bicarbonate solution and extracted with ethyl acetate (200 mL × 4). The organic phases were combined, washed sequentially with 100 mL of water and 100 mL of saturated saline, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography to afford (S)-N-Boc-2-hydroxymethylmorpholine (3.646 g, 97.7% yield) as colorless to light yellow liquid. Mass spectrum (ESI) m/z: 240.3 [M + 23]. 1H NMR (CDCl3, 400 MHz) δ 3.92-3.88 (m, 3H), 3.7-3.64 (m, 1H), 3.60-3.48 (m, 3H), 2.936 (m, 1H), 2.75 (m, 1H), 2.06 (m, 1H), 1.46 (s , 9H).
