反应详情

温度

0 °C

To a solution of L-leucine methyl ester hydrochloride (1.97 g) dissolved in DCM (32 mL) was added NMM (1.9 mL) and the mixture was stirred for 5 minutes before being cooled to 0° C. HOBt (4.0 g), EDAC (3.8 g) and L-α-hydroxyisocaproic acid (1.35 g) were then added sequentially to the reaction mixture. After 30 minutes at 0° C., the reaction was allowed to warm to room temperature and continued stirring overnight. The reaction mixture was concentrated and the resulting crude product was dissolved in EtOAc and washed 2×1.2N HCl, 2× saturated NaHCO3, brine, dried (MgSO4) and concentrated to yield the desired product (2.32 g, 82%). 1H NMR (300 MHz, CDCl3) δ 0.93-0.96 (m, 12H), 1.50-1.67 (m, 5H), 1.82-1.93 (m, 1H), 3.73 (s, 3H), 3.83 (bs, 1H), 4.11-4.18 (m, 1H), 4.57-4.64 (m, 1H), 7.07 (d, 1H).

1. waitAfter 30 minutes at 0° C.
2. temperatureto warm to room temperature
3. stirringcontinued stirring overnight
4. concentrationThe reaction mixture was concentrated
5. dissolutionthe resulting crude product was dissolved in EtOAc
6. washwashed 2×1.2N HCl, 2× saturated NaHCO3, brine
7. dry with materialdried (MgSO4)
8. concentrationconcentrated