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Information × Registration Number 0221U100671, 0119U002035 , R & D reports Title Bis(crown ethers) with photosensitive or rigid linkers capable to pre-organization: synthesis, structure and study of complexation with metal cations and organic substrates to search a new chemosensors popup.stage_title Head Kirichenko Tatiana I., Доктор хімічних наук Registration Date 08-01-2021 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description2 The object of research – synthesis, structure and complexing properties of bis(benzocrown ethers) containing quinoxaline or glycoluril fragments that bind crown ether cycles. The aim of this work – synthesis of bis (benzocrown ethers) containing quinoxaline or glycoluryl fragments that bind crown ether cycles based on crown-containing benzyl, study their structure and complexation with alkali metal cations. By boiling crown-containing benzyl with o-phenylenediamines in ethanol in the presence of PTSA with yields of 63–89%, bis(benzocrown ethers) containing quinoxaline fragments as a binding linker were obtained. It is shown that in the fluorescence spectra when alkali metal cations are added to solutions of bis(crown ethers) with an unsubstituted quinoxaline fragment, a significant increase in the fluorescence intensity (up to 5 times) is observed. By the methods of spectrophotometric and fluorescent titration were shown that the obtained crown-containing quinoxalines form with alkali metal cations complexes of composition 1:1. In some cases, complexes of 1: 2 (L: M) with a much lower stability constant are also observed with potassium and sodium cations. Compounds with 15-membered crown-ether cycles form the most stable sandwich-type complexes with rubidium and potassium cations, and 18-membered ones with cesium cation. Substances that are promising as chemosensors for the determination of cesium and potassium cations in the presence of large excess sodium cation have been identified. By boiling for 2-3 weeks with a Dean-Stark nozzle to remove water of crown-containing benzyl with urea in benzene or toluene in the presence of trifluoroacetic acid as a catalyst with a yield ≥ 70%, bis (benzocrown ethers) with glycoluryl fragments were obtained. Methyl groups on the nitrogen atoms of the glycoluryl moiety were introduced by methylation of the obtained compounds with methyl iodide in DMF in the presence of sodium hydride. Product Description popup.authors Bogashchenko Tetyana Yu. Kikot Leonid S. Kirichenko Tatiana I. Kulygina Katerina Yu. Lyapunov Alexander Yu. Jackovenko Irina S. popup.nrat_date 2021-03-17 Close