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Information × Registration Number 0220U101522, 0118U003393 , R & D reports Title Synthesis and properties of new potential complexons of cations of s and d elements based on aza(benzoaza)crown ethers derivatives and calix[4]arenes with substituents that include heterocyclic and aromatic fragments popup.stage_title Head Kirichenko Tatiana I., Доктор хімічних наук Registration Date 12-02-2020 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description2  Research object – Synthesis, structure and complexing properties of bis(benzoazacrown ethers) with flexible linkers. The structure and extraction ability of substituted 5,11,17,23-p-tert-butylcalix[4]arenes containing along the lower rim substituents consisting of fluoren-9-one, crown ethers and imidazoles. A purpose of work is synthesis of bis(benzoazacrown ethers) with flexible linkers, the study of their structure and complexation with cations of alkali and alkaline earth metals. The synthesis of calix[4]arenes containing fragments of nitrogen-containing heterocycles and the study of their extraction ability towards to cations of s-, d-, f-elements. Research methods – synthetic, UV, NMR spectroscopy, mass spectrometry, extraction. By the interaction of benzoaza-15-crown-5 with ditosylates of the corresponding glycols in acetonitrile in the presence of potassium carbonate, biscrown ethers) with benzoaza-15-crown-5 fragments and flexible methylene or polyoxyethylene bonding linkers were obtained in 65–82% yields. In the case of diethylene glycol and butanediol-1,4, instead of an intermolecular reaction, an intramolecular cyclization was observed involving the nitrogen atom of the crown ether to form spiro compounds. Using the spectrophotometric titration method, stability constants of complexes of bis(crown ethers) with alkali and alkaline earth cations were determined and the influence of the structure and length of the bonding linker on the stability and selectivity of the formed complexes was revealed. The synthesis of disubstituted at the lower rim p-tert-butyl calix[4]arene with fragments of imidazole and hydroxyfluoren-9-ones, including crowned macrocycles was carried out. The extraction properties of calixarenes with one and two dimethylimidazole substituents towards the picrates of some s- and d-metals were studied. A high selectivity of extraction of transition metal cations was found in comparison with alkali metal cations. Product Description popup.authors Alekseeva Olena O. Basok Stepan S. Kikot Leonid S. Kirichenko Tatiana I. Kulygina Katerina Yu. Lutsyuk Anatoliy F. popup.nrat_date 2020-04-02 Close