Benzoic Acid → [(1S)-1-[(2R)-2-(2,4-difluorophenyl)-2-oxiranyl]ethyl]benzoate

Participants

Reaction Steps

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, under ice-cooling, 63.3 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 mixture were added 800 ml of ethyl acetate and 500 ml of water to fractionate and the aqueous phase was extracted with 200 ml of ethyl acetate. The organic phases were collected, washed successively with water and with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and concentrated. The residue was purified by using silica gel chromatography (gradient eluent; hexane:ethyl acetate=15:1→7:1) to give 19.2 g of [(1S)-1-[(2R)-2-(2,4-difluorophenyl)-2-oxiranyl]ethyl]benzoate as a colorless oil.

Provenance & Evidence