Synthesis Of Thermoregulated Acid Ionic Liquids And Their Catalytic Property Of α-Pinene Reactions

α-pinene is a kind of important natural products, taking it as a raw material canproduce terpinyl acetate and terpineol. At present, the process has a lot ofshortcomings, for example, the equipment corrosion seriously, environment pollutionand catalyst repeated use difficult. In view of the above questions, this topicsynthesized the new thermoregulated acid ionic liquids. They were used to catalyzeα-pinene direct esterification and hydration. It improved the activity and selectivity ofthe reaction, completed the reaction-separation integration of the reaction process andthe recycling of the catalyst.22thermoregulated-acidic ionic liquid was synthesized to octadecylaminepolyoxyethylene ether series （AC1810, AC1815, AC1820, AC1830） as the rawmaterial, all could with α-pinene form thermoregulated biphasic system, and thecritical solution temperature was relevant with the volume ratio of them and the degreeof polymerization. They were characterized by FT-IR,¹H NMR and¹³C NMR. Theacid type of ionic liquids were determined by adopting infrared spectrometry usingpyridine as probe. Synthesis of ionic liquids were Brφnsted acid. Their acid value weredetermined by alkali neutralization, found the acid strength was decided by anionkinds and the degree of polymerization.The different types of ionic liquid were used as a catalyst in the directesterification of α-pinene. It was found that the functionalized ionic liquidpolyoxyethylene octadecylamine ether tetrafluoroborate （[PAC18n][BF₄]） was moresuitable for the reaction. Then this study studied the polymerization degree, and foundthe catalytic properties of ionic liquid was the best, when n=15. So we choose [PAC1815][BF₄] as the catalyst. The influences of factors on α-pinene reactions were investigated. The optimum conditions were obtained. The optimum conditions weren（α-pinene）: n（ionic liquid）: n（chloroactic acid）: n（acetic acid）=1:0.06:1.2:4,n（α-pinene）=0.05mol, reaction temperature30℃and reaction time10h. Underabove conditions, the conversion of α-pinene was91.76%and the selectivity ofterpinyl acetate was38.94%. When the catalyst was reused for5times, α-pineneconversion and selectivity of terpinyl acetate were still89.14%and35.90%,respectively.The different types of ionic liquid were used as a catalyst in the direct hydrationof α-pinene. It was found that the ionic liquid polyoxyethylene octadecylamine ethersulphuric （[AC1815][HSO₄]） was an excellent catalyst for the synthesis of terpinol.The influences of factors on α-pinene reactions were investigated. The optimumconditions were n（α-pinene）: n（ionic liquid）: n（chloroactic acid）: n（water）=1:0.05:1:5, n（α-pinene）=0.06mol, reaction temperature80℃and reaction time8h.Under above conditions,the conversion of α-pinene was94.0%and the selectivity ofterpinyl acetate was59.2%. When the catalyst was reused for5times, α-pineneconversion and selectivity of terpinyl acetate were still91.5%and58.4%, respectively.The catalyst exhibited excellent catalytic activity and reusability.All in all, this kind of thermoregulated acidic ionic liquid could formthermoregulated biphasic system with α-pinene. As catalysts of α-pinene acid catalyticreaction showed effectively catalytic activity and reusability. The process realized thereaction-separation integration, for future research provided a new approach.