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Catalytic ring opening reactions of α-epoxyketones catalyzed by rare earth metal triflates as heterogeneous，and highly efficient catalyst in methanol or ethanol solution at room temperature resulted in the formation of α-hydroxyl-β-methoxyketones through Cβ-O bond cleavage in excellent yields.Whereas the nature and location of the additional substituent affected the rate of ring opening，increasing the temperature had little or no effect on the rate of reactions，meanwhile prolonging the reaction time lead to higher yields and better yields were also got with Yb(OTf)3 than other rare earth triflates.Most of the reactions were carried under ambient temperature conditions and got remarkable yields.Pure products were isolated from reaction mixtures by flash chromatography with petroleum ether: ethyl acetate 100∶1 as the eluent. α,β-Epoxyketones A.K.A Chalcone epoxides were easily synthesized in my lab by myself.A one-pot consecutive process has been developed for chalcone epoxide synthesis that allows compounds to be prepared without having to go through all the processes of isolating and purifying the intermediates.The strategy utilizes consecutive Claisen Schmidt condensation and epoxidation reactions to prepare chalcone epoxides from substituted benzaldehydes and acetophenones in good yields.Rare earth metal triflates and alcohols such as methanol and ethanol were readily available in my lab.