反应详情

To a stirred solution of 15 (3.30 g, 17.9 mmol) in methylene chloride (150 mL) and triethylamine (5.01 mL, 3.61 g, 35.7 mmol), was added dropwise triethylsilyl trifluoromethanesulphonate (4.07 mL, 4.72 g 17.9 mmol) at 0° C. After 20 minutes, N-bromosuccinimide (3.53 g, 19.8 mmol) was added, and the cooling bath was removed. Water (50 mL) was then added, and the mixture was extracted with methylene chloride (3×100 mL). The organic phase was dried over anhydrous MgSO4, concentrated under reduced pressure, and the residue was purified by column chromatography (3-10% ethyl acetate/hexane) to give 3.42 g (13.0 mmol; 73% yield) of 16. 1H NMR MHz, CDCl3) δ 0.96 (3H, t, J=7.4 Hz), 1.47 (2H, m), 1.60-1.66 (6H, m), 4.16 (2H, t, J=6.7 Hz), 4.50 (2H, s). 13C NMR (100 MHz, CDCl3) δ 13.7, 19.2, 21.2, 30.5, 33.2, 35.1, 65.5, 170.4, 197.6. MS (EI) m/z 264 (40, M+), 262 (39, M+), 208 (20), 206 (20), 190 (56), 188 (54), 183 (71), 169 (100); exact mass (ESI) calculated for C10H15O3BrNa ([M+Na]+) 285.0102, found 285.0114.

1. customthe cooling bath was removed
2. additionWater (50 mL) was then added
3. extractionthe mixture was extracted with methylene chloride (3×100 mL)
4. dry with materialThe organic phase was dried over anhydrous MgSO4
5. concentrationconcentrated under reduced pressure
6. customthe residue was purified by column chromatography (3-10% ethyl acetate/hexane)