反应详情

To a mixture of 104A (2.33 g, 18.9 mmol) and dibromoethane (6.5 mL, 75.7 mmol) in a mixture of acetone (80 mL) and water (20 mL) at room temperature was added potassium carbonate (10.46 g, 75.7 mmol). The mixture was heated at reflux for 3 days. HPLC indicated that the reaction was complete, and the acetone was removed under reduced pressure. The aqueous residue was extracted with DCM, washed with water, and dried over anhydrous sodium sulfate. Concentration under reduced pressure followed by purification by silica gel chromatography afforded 104B (2.22 g, 79%). HPLC retention time=2.07 min. (Condition B) and LC/MS M+1=150.08. 1H-NMR (500 MHz, CDCl3) δ 2.91 (s, 3H), 3.28 (t, 2H), 4.33 (t, 2H), 6.70 (t, 1H, J=7.5 Hz), 6.72 (d, 1H, J=7.5 Hz), 6.82 (d, 1H, J=7.5 Hz), and 6.89 (t, 1H, J=7.5 Hz).

1. temperatureThe mixture was heated
2. temperatureat reflux for 3 days
3. customthe acetone was removed under reduced pressure
4. extractionThe aqueous residue was extracted with DCM
5. washwashed with water
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationConcentration under reduced pressure
8. customfollowed by purification by silica gel chromatography