反应详情

To a solution of 75.4 g (F.W. 353.168, 213 mmol) of 4-bromo-2-(3,5-dimethoxyphenoxy)benzoic acid (22) in 300 mL of tetrahydrofuran was added 8.9 g (F.W. 37.83, 235 mmol) of sodium borohydride portionwise at room temperature and then, 31 mL (F.W. 141.93, d=1.154, 252 mmol) of boron trifluoride diethyl etherate was added thereto dropwise. The resulting solution was stirred at room temperature for one hour. To this reaction solution was added 200 mL of ice water slowly. The resulting solution was extracted with ethyl acetate and the extract was washed with a saturated sodium chloride aqueous solution three times. After drying with anhydrous magnesium sulfate, the solvent was removed under reduced pressure. The residue was recrystallized from benzene-diisopropyl ether to obtain 46.6 g (64%) of alcohol (23). (TLC; ethyl acetate:hexane=1:4).

1. extractionThe resulting solution was extracted with ethyl acetate
2. washthe extract was washed with a saturated sodium chloride aqueous solution three times
3. dry with materialAfter drying with anhydrous magnesium sulfate
4. customthe solvent was removed under reduced pressure
5. customThe residue was recrystallized from benzene-diisopropyl ether