反应详情

A mixture of 6.6 g of 2-ethoxycarbonyl-2,2-difluoro-1-phenylethyl 1-adamantanecarboxylate, prepared in Synthesis Example 1-5, 20 g of 1,4-dioxane, and 2.5 g of 25 wt % sodium hydroxide was stirred for 2 hours. Water, 30 g, was added to the reaction solution, which was washed with n-hexane, obtaining an aqueous solution of sodium 3-(adamantane-1-carbonyloxy)-2,2-difluoro-3-phenylpropionate. To this solution, 95 g of an aqueous solution of 4-tert-butylphenyldiphenylsulfonium methylsulfate and 100 g of methylene chloride were added. After stirring for 30 minutes, the organic layer was taken out, washed with water, and concentrated under reduced pressure. Methyl isobutyl ketone was added to the concentrate, which was concentrated again. Diisopropyl ether was added to the concentrate for crystallization. The resulting solid was dried in vacuum, obtaining 5.4 g of the target compound, 4-tert-butylphenyldiphenylsulfonium 3-(adamantane-1-carbonyloxy)-2,2-difluoro-3-phenylpropionate as white crystals (yield 52%).

1. washwas washed with n-hexane