反应 #2171071

反应方程式

9a

15-Hydroxy-4,7,10,13-tetraoxapentadecanoic Acid tert-Butyl Ester

phosphorus tribromide

Water

→

pure product 10a

收率 85.1%

15-Bromo-4,7,10,13-tetraoxapentadecanoic Acid tert-Butyl Ester

收率 85.1%

溶剂

pyridine

反应条件

后处理

1. 1
   其他at 0° C.
2. 2
   萃取the organics were extracted into methylene chloride (3×25 mL)
3. 3
   洗涤The combined organic layers were washed with sodium bicarbonate (25 mL)
4. 4
   干燥dried over magnesium sulfate
5. 5
   其他the solvent was removed in vacuo
6. 6
   其他The residue was purified on silica gel using neat ethyl acetate as the eluant

实验过程

To a stirred solution of 9a (1.0 g, 3.11 mmol) in 1 mL of pyridine at 0° C. was slowly added phosphorus tribromide (0.116 mL, 1.22 mmol) via syringe (Bradshaw et al., J. Het. Chem., 27:347-349 (1990)). The solution was allowed to stir overnight, at which time TLC analysis indicated that the reaction was complete. Water (25 mL) was poured into the reaction vessel and the organics were extracted into methylene chloride (3×25 mL). The combined organic layers were washed with sodium bicarbonate (25 mL), followed by brine (25 mL), dried over magnesium sulfate, and the solvent was removed in vacuo. The residue was purified on silica gel using neat ethyl acetate as the eluant to give 400 mg (35% yield) of pure product 10a (FIG. 7). 1H NMR: 1.37 (s, 9H), 2.43 (t, 2H, J=6.4 Hz), 3.40 (t, 2H, J=6.4 Hz), 3.53-3.61 (m, 12H), 3.64 (t, 2H, J=6.4 Hz), 3.74 (t, 2H, J=6.4 Hz). 13C NMR: 27.90, 30.13, 36.06, 66.68, 70.17, 70.31, 70.32, 70.39, 70.46, 70.99, 80.22, 170.65.

来源