1174913-80-4

Step 3. tert-Butyl (S)-2-(azidomethyl)morpholine-4-carboxylate (1.0 eq.) was dissolved in ethanol (0.1 M) under argon protection. To this solution was added Pd/C catalyst (0.20 eq.), followed by three evacuations of the reaction system and replacement with hydrogen gas. The reaction mixture was stirred at room temperature and under atmospheric pressure hydrogen atmosphere (using a hydrogen balloon) for 24 hours. Upon completion of the reaction, the hydrogen was removed by evacuation and the reaction system was replaced with argon. The reaction mixture was filtered through a diatomaceous earth pad and concentrated under reduced pressure to afford tert-butyl (R)-2-(aminomethyl)morpholine-4-carboxylate as a white solid in 91% yield.LCMS analysis showed (m/z) [M+H]+ = 217.1 and retention time (Rt) = 0.43 min.

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