反应详情

温度

0 °C

Compound 5 (4.00 g, 9.36 mmol) was dissolved in acetone (10 mL) and 2,2-dimethoxypropane (5.75 mL, 46.8 mmol) was added. The solution was cooled to 0° C. and methanesulfonic acid (2 drops) was added. The solution was stirred for 15 min and Et3N (1 mL) was added. The acetone was evaporated and the residue was dissolved in EtOAc, washed with water and brine, dried (MgSO4), filtered and concentrated. The residue was purified via column chromatography on silica gel (EtOAc/hexanes) to give the title compound as a white solid. 1H NMR (CDCl3) δ 6.21 (d, J=8 Hz, 1H), 4.65-4.59 (m, 2H), 4.45-4.44 (m, 1H), 3.94 (s, 3H), 3.89-3.85 (m, 1H), 3.76-3.73 (m, 1H), 2.61-2.55 (m, 1H), 2.52 (s, 3H), 2.40-2.34 (m, 1H), 1.85 (br s, 1H), 1.65-1.57 (m, 2H), 1.49 (s, 3H), 1.28 (s, 3H); LCMS 2.54 min, 468 (M+H).

1. customThe acetone was evaporated
2. dissolutionthe residue was dissolved in EtOAc
3. washwashed with water and brine
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified via column chromatography on silica gel (EtOAc/hexanes)