In this paper, we successively apply the “fluorous biphase system” (FBS) technique to the reactions of cyclopropyl aryl ketones with α-ketoacetic acids catalyzed by C₈F₁₇SO₃H (30 mol%) using perfluorodecalin (C₁₀F₁₈, cis- and trans-mixture) and DCE as a co-solvent to give the corresponding products 5,6-dihydropyran-2-ones in good yields. Moreover, the reaction system can be performed for several times without reloading the catalyst and the fluorous solvent.