反应详情

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

1. extractionthe aqueous layer was extracted with 200 ml of ethyl acetate
2. washwashed with water and saturated aqueous solution of sodium chloride
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated
5. customThe residue was purified by silica gel chromatography (eluate; hexane:ethyl acetate=15:1 to 7:1)