The Study Of Acylation And Ritter Reaction Catalyzed By Functional Ionic Liquids

Ionic liquids developed in recent years is a new type of the green solvent and efficient catalyst. It has been applied in many organic reaction with a good solvent effects and catalytic properties, and received an extensive attention. So in this paper, Ionic liquids was as solvent and catalyst used in Acylation and Ritter reaction[Bmim]BF4 and [Bmim]PF6 ionic liquids were synthesized and characterized by FT-IR, 1H NMR, the p-methoxyacetophenone was synthesized by Acylation of Anisole with Acetic Anhydride using heteropolyacid as catalyst in [Bmim]BF4 and [Bmim]PF6 ionic liquids. The experiment has been investigated under the reaction conditions such as the type of ionic liquids, reaction temperature and reaction time. The cyclical character about the system of heteropolyacid and ionic liquids also were studied. In Acylation of Anisole with Acetic Anhydride, [Bmim]BF4 had the better result, the reaction temperature was 50℃, the reaction time was 6 h, and the yield was up to 40.89 %, the purity of product was higher than 97 % (GC). The system of heteropolyacid and ionic liquids could be recycled by distillation and reused 6 times without noticeably decreasing the catalytic activity.Three Lewis acidic ionic liquids which were [Bmim]Cl–Al2Cl6, [Bmim]Cl–Fe2Cl6, [Bmim]Cl–Zn2Cl4, were synthesized and characterized by FT-IR, 1H NMR, the purity of [Bmim]Cl was 99.5 % by 0.1 mol/L AgNO3 solution. p-acetylanisole was synthesized using Lewis acidic ionic liquids as catalysts and characterized by FT-IR, 1H NMR, 1C NMR, the value of melting point determination was 38.5~39.2℃, the purity of product was higher than 99 % (GC). According to the study of catalytic activity and the reusability of various ionic liquids, [Bmim]Cl-AlCl3 was chosen to synthesize p-acetylanisole as the catalyst. The effects of the reaction conditions on the reaction results, such as molar ratio of anisole and Acetic Anhydride, reaction time, reaction temperature were examined and the optimal conditions were obtained. The optimal conditions were as follows: n (anisole)∶n (Acetic Anhydride)=1∶1.5, 60℃, 6 h. Under the optimal reaction conditions, the conversion could be 78.8%. The ionic liquids could be repeatedly used for five times after distillation and vacuum drying without considerable loss of activity.Four Br?nsted acidic ionic liquids which were [Bmim][HSO4], [Bmim][H2PO3], [Emim][HSO4], [Epy][HSO4], were synthesized and characterized by FT-IR, 1H NMR. The H0 was determined using Hammett function, the acidity of [EPy] HSO4 was the best, the H0 was up to -0.04. Then N-Tert-Butylphenylacetamide was synthesized using Ritter reaction by Br?nsted acidic ionic liquids and characterized by FT-IR, 1H NMR, 1C NMR, the purity of product was 100 % (HPLC). Next step N-Tert-Butylacrylamide was synthesized and characterized by FT-IR, 1H NMR, 1C NMR, the purity of product was 90.75 % (HPLC). According to the study of catalytic activity and the reusability of various ionic liquids, [EPy] HSO4 as the catalyst was chosen to synthesize N-Tert-Butylphenylacetamide, The optimal conditions were as follows: 50℃, 5 h. Under the optimal reaction conditions, the conversion could be 84.2%. The ionic liquids could be repeatedly used for six times after distillation and vacuum drying without considerable loss of activity.