Synthesis
GENERAL STEPS: N-Boc-L-alanine (5.0 g, 26.4 mmol) was dissolved in anhydrous THF at -10 °C and triethylamine (3 mL, 21.12 mmol) and ethyl chloroformate (2.5 mL, 26.4 mmol) were added sequentially under stirring. The reaction mixture was continued to be stirred at this temperature for 1 hour. Subsequently, ammonia (NH3) was passed into the reaction system for 1.5 hours. The reaction mixture was brought to room temperature and stirred overnight. After completion of the reaction, the THF solvent was removed by distillation under reduced pressure. Saturated sodium chloride solution (40 mL) was added to the residue and extracted with ethyl acetate (5 x 40 mL). The organic phases were combined, washed with 0.5 M hydrochloric acid (2 x 30 mL), dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give N-Boc-D-alaninamide.
References
[1] Tetrahedron, 1999, vol. 55, # 42, p. 12301 - 12308
[2] Tetrahedron Letters, 2007, vol. 48, # 4, p. 603 - 607
[3] Synthetic Communications, 2013, vol. 43, # 7, p. 993 - 1006
[4] Bulletin of the Chemical Society of Japan, 1988, vol. 61, # 7, p. 2647 - 2648
[5] Tetrahedron Asymmetry, 2013, vol. 24, # 24, p. 1572 - 1575
