反应详情

To an ice-cooled solution of (1R)-1-[(2R)-2-(2,4-di-fluorophenyl)-2-oxiranyl]ethanol (16.1 g) in tetrahydrofuran (320 ml) were added triphenylphosphine (63.3 g), benzoic acid (29.5 g) and diethyl azodicarboxylate (42.0 g). The mixture was stirred at room temperature for 6 hours under an argon atmosphere. After ethyl acetate (800 ml) and water (500 ml) were added thereto, the separated aqueous layer was extracted with ethyl acetate (200 ml). The combined organic layers were washed with water and a saturated aqueous solution of sodium chloride successively, dried over magnesium sulfate and concentrated. The residue was purified by silica gel chromatography (eluent: hexane/ethyl acetate=15/1 to 7/1) to give [(1S)-1-[(2R)-2-(2,4-difluorophenyl)-2-oxiranyl]ethyl] benzoate (19.2 g) as a colorless oily substance.

1. extractionthe separated aqueous layer was extracted with ethyl acetate (200 ml)
2. washThe combined organic layers were washed with water
3. dry with materiala saturated aqueous solution of sodium chloride successively, dried over magnesium sulfate
4. concentrationconcentrated
5. customThe residue was purified by silica gel chromatography (eluent: hexane/ethyl acetate=15/1 to 7/1)