92235-34-2

24424-99-5

4128-00-1

92235-34-2

Step 1: (S)-3-Amino-2-pyrrolidinone (3.1 g, 32 mmol) was dissolved in methanol (130 mL) at room temperature and triethylamine (16 mL) and di-tert-butyl dicarbonate (7.7 g, 35.2 mmol) were added sequentially. The reaction mixture was stirred at room temperature overnight and then heated to reflux for 2 hours. After completion of the reaction, the solvent was removed by concentration under reduced pressure and the residue was purified by column chromatography (eluent: ethyl acetate) to afford (S)-tert-butoxycarbonyl-3-amino-2-pyrrolidinone (5.0 g, 78% yield) as a white solid.