Ionic Liquid as Catalyst for Synthesis 2-(4-Ethylbenzoyl)benzoic Acid

The effects of reaction conditions such as the proper proportion between [Bmim]Cl and AlCl3 in the ionic liquid,the molar ratio of ethylbenzene and phthalic anhydride,temperature,and reaction time on synthesis of 2-(4-ethylbenzoyl)benzoic acid were investigated. When [Bmim]Cl-AlCl3 was used as the catalyst,phthalic anhydride conversion of 100% and 2-(4-ethylbenzoyl)benzoic acid yield of 97.14% can be obtained under the conditions:the component of the ionic liquid was:n(AlCl3) ∶ n([Bmim]Cl)=1 ∶ 3,n(ionic liquid) ∶ n(ethylbenzene) ∶ n(phthalic anhydride) = 1 ∶ 1 ∶ 1,the reaction temperature was 50℃ and the reaction time was 4 h. The process can react without solvents.