反应详情

A solution of compound 3 (0.19 g, 0.695 mmol) in dry DMF (3 mL) was treated with N-bromosuccinimide (0.124 g, 0.695 mmol) in DMF (2 mL) at 0° C. over a period of 10 minutes. The reaction was stirred at the same temperature for 3.5 h. The reaction was diluted with water (50 mL) and the product was extracted into ethyl acetate (2×20 mL). The combined ethyl acetate layer was washed with water (2×20 mL), brine (15 mL) and dried (Na2SO4). Solvent was evaporated and the crude mixture was purified by column chromatography on silica gel (ethyl acetate:hexanes, 1:9) to obtain compound 4 (0.225 g, 92%) as a syrup. 1H NMR (CDCl3) δ 7.16-7.05 (m, 2H), 6.60-6.52 (m, 1H), 3.96 (s, 4H), 3.64-3.55 (m, 1H), 3.20 (t, 2H, J=5.7 Hz), 2.69 (t, 2H, J=6.0 Hz), 1.91-1.54 (m, 10H); ESI-MS (m/z, %): 352, 354 (MH+, 100).

1. extractionthe product was extracted into ethyl acetate (2×20 mL)
2. washThe combined ethyl acetate layer was washed with water (2×20 mL), brine (15 mL)
3. dry with materialdried (Na2SO4)
4. customSolvent was evaporated
5. customthe crude mixture was purified by column chromatography on silica gel (ethyl acetate:hexanes, 1:9)