Potentiometric studies of complex formation of amidopyridine macrocycles bearing pendant arms with proton and heavy metal ions in aqueous solution
| Autor: | B. V. Egorova, Yu. V. Fedorov, Anastasia D. Zubenko, Olga A. Fedorova, Dmitry E. Arkhipov, Stepan N. Kalmykov, Yu. V. Nelubina, Maxim Oshchepkov |
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| Rok vydání: | 2017 |
| Předmět: |
inorganic chemicals
010405 organic chemistry Ligand Metal ions in aqueous solution Potentiometric titration Inorganic chemistry Ether Protonation 010402 general chemistry 01 natural sciences 0104 chemical sciences Inorganic Chemistry Metal chemistry.chemical_compound chemistry visual_art Amide Pyridine Polymer chemistry Materials Chemistry visual_art.visual_art_medium Physical and Theoretical Chemistry |
| Zdroj: | Polyhedron. 124:229-236 |
| ISSN: | 0277-5387 |
| DOI: | 10.1016/j.poly.2016.12.037 |
| Popis: | A novel pyridine-azacrown ether amide macrocycles comprising pyridine or carboxylic pendant arms were synthesized. The protonation constants of the compounds and the stability constants of their complexes with a wide range of metal ions (Ag+, Cu2+, Zn2+, Cd2+, Ni2+, Pb2+, Y3+, Eu3+, Lu3+) were determined by potentiometric method. The different complexes of macrocycles with cations, including HML, ML and ML(OH)n were found to form. The increase of the stability of the complexes provides the presence of carboxyl substituents in pyridine-azacrown ether amide macrocycles; the values for the Cu2+, Ni2+ and Pb2+ complexes of ligand containing three carboxylic arms are exceptionally high. Single crystal structures of a few complexes with Cu2+ and Pb2+ were determined. In all complexes, the metal centre exhibit a strong coordination with amine N-atoms and arm’s ligand groups. The rigid structure of pyridine-2,6-dicarbamide fragment and an open macrocyclic cavity provide a possibility to fast kinetics of complex formation. |
| Databáze: | OpenAIRE |
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