反应详情

N,N-Diisopropylethylamine (15.10 g, 116.8 mmol) and HATU (10.77 g, 28.34 mmol) were added to a suspension of Boc-Asp-(OBzl)-OH (7.61 g, 23.54 mmol) and methylamine hydrochloride (5.03 g, 74.50 mmol) in DMA (31 mL). After stirring at room temperature for 18 h, the reaction mixture was diluted with CH2Cl2 and washed with saturated NaHCO3. The organic layer was washed with H2O several times, dried over Na2SO4, filtered, and concentrated. The residue was purified via silica gel chromatography with 0% MeOH in CH2Cl2 grading to 4% MeOH in CH2Cl2 to afford the titled product (6.2 g, 78%) as a white solid. 1H-NMR (CDCl3) δ: 1.471 (9H, s), 2.730 (1H, m), 2.818 (3H, d, J=4.8 Hz), 3.120 (1H, m), 4.520 (1H, s), 5.156 (2H, m), 5.660 (1H, s), 6.430 (1H, s), 7.378 (5H, m). LC-MS (ES) m/e 337.2 (M+H)+.

1. washwashed with saturated NaHCO3
2. washThe organic layer was washed with H2O several times
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was purified via silica gel chromatography with 0% MeOH in CH2Cl2 grading to 4% MeOH in CH2Cl2