...Amino Acid Derivatives through Aza-Michael Addition of NH...
Purification was conducted at 130 ◦C and 4 × 10−3 bar pressure via distillation in vacuo to give 3 (12.44 g, 72%) as a colorless oil. IR (νmax, cm−1): 2968, 1720 (C=O), 1701 (C=O). 1H NMR (700 MHz, CDCl3): δH ppm 1.39 (s, 9H, C(CH3)3), 3.66 (s, ...