Benzyl 2,2,2-trichloroacetimidate → (3S)-3-(benzyloxy)butanoic acid ethyl ester

Beteiligte Stoffe

Reaktionsschritte

Under a nitrogen atmosphere, to a solution of (S)-(+)-3-hydroxybutyric acid ethyl ester (100 g, 0.76 mol) in methylene chloride (1.0 L), benzyl 2,2,2-trichloroacetoimidate (381 g, 1.5 mol) and trifluoromethanesulfonic acid (6.7 mL, 76 mmol) were gradually added, and the mixture was stirred at room temperature overnight. The precipitated solid was filtered, and after the mother liquid was successively washed with a saturated aqueous sodium hydrogencarbonate solution, water and saturated brine, it was dried with sodium sulfate and the solvent was distilled off under reduced pressure. Hexane was added to the residue, and after the solid was filtered again, the solvent of the mother liquid was distilled off under reduced pressure to give (3S)-3-(benzyloxy)butanoic acid ethyl ester (339 g) as a mixture. The present compound was used for the subsequent reaction without further purification.

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