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Lactone crown ether compound due to its particular cyclic structure, has been widely used in various fields of analysis, synthesis, and catalysis. Glycol, multi-glycol dihalide, the acid halide of the dibasic acid, or hydroxy carboxylic acid salts and other non-cyclic starting materials as the raw material, via an intramolecular or intermolecular cyclization reaction lactone crown ether is the more common methods. Paper studies in the Al-Mg-based composite-based catalyst under catalytic conditions embedded in γ-butyrolactone (GBL) by ring expansion reaction Step Synthesis lactone crown ether, epoxy alkane, the synthesis method is novel and simple steps . And explore the template agent, added to the above reaction with the Template Synthesis lactone type crown ether. Experiments the following conclusions: (1) to explore in the LE series under catalytic conditions, ethylene oxide embedded GBL by expanding the step synthesis lactone ring crown ether reaction. The structure of the product was analyzed by FT-IR, ESI-MS, HPLC-(ESI) MS characterization methods confirmed that the crown ether to generate the target product lactone. LE series catalyst screening, with an emphasis on the appropriate reaction conditions to improve the conversion rate of the GBL. I.e. under the catalytic action of the catalyst of LE-4, added in an amount of 1% of the target product, the system initial pressure of 0 MPa (gauge pressure), reaction temperature is 155 ~~ 165 ° C, n-(EO): N (GBL) = 11: 1, to maintain system pressure of 0.5 ~ 0.6 MPa, the conversion rate of the raw material of GBL is as high as 91.2%. (2) the catalytic effect of the catalyst LP, embedded in the the GBL by ring expansion step synthesis lactone crown ether reaction of propylene oxide (PO) to explore. By the FT-IR of the crude product after the reaction, HPLC-(ESI) MS, and the complexation properties of the comprehensive analysis, confirmed that the generate target product lactone crown ether. Focus Discover GBL conversion rate suitable conditions: 150 to 160 ° C, from 0.5 to 0.6 MPa, n (PO): n (GBL) = 13: 1 under conditions of GBL conversion rate was 90.4%. (3) by the revelation of template synthesis of macrocyclic compounds, added to in the above synthesis method template agent, to explore the distribution of the product. Emphasis on the existence and distribution of KI, KBr, KCl, acetonitrile as template the target product lactone crown ether. More appropriate template agent KCl as determined by ESI-MS analysis. And under the reaction conditions in the presence or absence of templating agent, on the catalytic activity, the reaction temperature, GBL conversion rate, byproduct content comparison. The results show that: the reaction temperature under the conditions of existence of the templating agent (KCl) a decrease of 10 to 20 ° C, raw materials GBL conversion rate was increased to 7.45%, the catalytic activity is increased by 3.62%, while the content of the byproducts also increased by 4.76%.
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