反应详情

To a solution of proline-tert-butyl ester (47) (2.00 g, 12 mmol, in CH2Cl2 (15 ml) was added N-carbobenzyloxy-2-methylalanine (3.05 g, 13 mmol), HOBT (2.36 g, 17 mmol) and EDC (3.43 g, 18 mmol) and the solution was stirred at room temperature under N2 for 48 hours. The solvent was evaporated, the crude material dissolved in EtOAc and washed with 0.5N NaHSO4 (2×), saturated NaHCO3 (2×) and brine and was dried over anhydrous Na2SO4, filtered and evaporated to give a white solid (4.68 g, 100%). 1H-NMR (500 MHz, CDCl3) δ 1.20-2.15 (m, 4H), 1.43 (s, 9H), 1.59 (d, 6H), 3.21-3.79 (m, 2H), 4.35 (br s, 1H), 4.82-5.19 (m, 3H), 5.74 (br s, 1H), 7.17-7.49 (m, 5H). Analytical HPLC (C18 column) 10.66 min. LC-MS (ES+) m/e=391.3 (M+H).

1. customThe solvent was evaporated
2. dissolutionthe crude material dissolved in EtOAc
3. washwashed with 0.5N NaHSO4 (2×), saturated NaHCO3 (2×) and brine
4. dry with materialwas dried over anhydrous Na2SO4
5. filtrationfiltered
6. customevaporated