Hydrochloric Acid → 1,3-Diacetoxy-2-(2,4-difluorophenyl)-2-propanol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Under an atmosphere of argon, 22.5 g of 2,4-difluorobromobenzene was dissolved in 200 ml of diethyl ether and to the resulting solution was added dropwise 73 ml of 1.63M n-hexane solution of n-butyllithium at -30° C. The resulting liquid was stirred for 1 hour and stored at -60° C. This liquid was carefully added dropwise using an injection cylinge to 150 ml of diethyl ether solution of 17.4 g of 1,3-diacetoxyacetone which was previously cooled to -30° C. After the resulting liquid was stirred at -60° C. for 2 hours, a temperature thereof was gradually raised to room temperature. Then, the reaction mixture was transferred to 100 ml of 1.2N aqueous solution of hydrochloric acid at 5° C. or below, and the organic layer was separated therefrom and the aqueous layer was extracted twice with 100 ml of ethyl acetate. The organic layers were combined and washed with saturated aqueous solution with sodium chloride, dried over anhydrous magnesium sulfate. The resulting organic layer was filtered and the solvent was removed under reduced pressure. Thus obtained concentrate was purified by column chromatography on silica gel (hexane:ethyl acetate=1:1) to give 8 g of the desired compound.

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