反应详情

A solution of (S)-3-(4-hydroxy-phenyl)-2-methoxy-propionic acid (20 g, 100 mmol) in 3 A ethanol (140 mL) was treated dropwise with concentrated sulfuric acid (5.7 mL)) and stirred at room temperature overnight. The solution was concentrated and is water (110 mL) was added. Sodium bicarbonate was added to bring the pH to 7–8. The mixture was extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with 20% NaCl solution (50 ml), dried (MgSO4), filtered, and concentrated to a golden oil (18 g, 80%). 1H-NMR (CDCl3): 7.1(d, 2H); 6.7(d, 2H); 4.2(m, 2H); 3.9(m, 1H); 3.6(s, 3H); 2.95(m, 2H); 125(t, 3H). MS (ES): 223.2 (M−1).

1. concentrationThe solution was concentrated
2. additionwas added
3. additionSodium bicarbonate was added
4. extractionThe mixture was extracted with ethyl acetate (3×50 mL)
5. washThe combined organic layers were washed with 20% NaCl solution (50 ml)
6. dry with materialdried (MgSO4)
7. filtrationfiltered
8. concentrationconcentrated to a golden oil (18 g, 80%)