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Information × Registration Number 0223U000375, 0122U000344 , R & D reports Title Synthesis and complexing properties of bis(benzocrown ethers) with a rigid linker that reorganizes crown ether cycles to interact with substrates popup.stage_title Head Kyrychenko Tetiana I., Доктор хімічних наук Registration Date 06-01-2023 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description2 The object of research – the reaction of phenols with benzyl, which leads to the formation of coumaranocumarones. The aim of this work – development of a convenient method for the synthesis of new bis(benzocrown ethers) with a rigid linker based on diphenylcoumaranocoumarone, which binds crown ether rings. The interaction of oxybenzocrown ethers with benzyl in the system 66% CHCl3, 17% glacial CH3COOH, 17% conc. HCl was studied. It is shown that the reaction products form stable complexes or clathrates with acetic acid. The influence of various acids, solvents, and temperature on the yield and duration of the process of formation of a rigid condensed fragment of coumarone was studied on the model reaction of benzyl with 3,4-dimethoxyphenol. During the reaction in polyphosphate acid or a mixture of sulfuric and phosphoric acids, it is not possible to obtain the expected product, the reaction stops at the first stage. Heating the reagents at 60 °C in a mixture of acetic and hydrochloric acids with the addition of chloroform, as described earlier, allows you to isolate the product with a yield of 53%, but requires prolonged heating - 96 hours. When replacing acetic acid with dioxane, it is possible to achieve better homogeneity of the reaction mixture. However, the yield of the product when heated at 60 °C for 96 and 60 hours is 37–39%. Raising the temperature to 70 °C allows to reduce the heating time to 50 hours and isolate the product with a yield of 49.57%.   Product Description popup.authors Bogashchenko Tetyana Yu. Kyrychenko Tetiana I. Kulygina Katerina Yu. Chepelev Olexander V Jackovenko Irina S. popup.nrat_date 2023-01-06 Close