CHEMICAL STRATEGY FOR THE SYNTHESIS OF CHALCONES AS DEHYDROACETIC ACID DERIVATIVES AND THEIR LANTANIUM(III) COMPLEXES

• Дата: 2024
• Автори: Chernii, Viktor, Tretyakova, Iryna, Fedosova, Natalia, Denisenko, Iryna, Dovbii, Yan, Kobylinska, Natalia
• Формат: Стаття
• Мова: English
• Опубліковано: V.I.Vernadsky Institute of General and Inorganic Chemistry 2024
• Онлайн доступ: https://ucj.org.ua/index.php/journal/article/view/643
• Назва журналу: Ukrainian Chemistry Journal

In this study, a series of condensed deri­vatives of dehydroacetic acid with a chalcone structure were synthesized by the Knevenagel reaction using isopropanol as a solvent. The yield of the reaction was 30–75%. It was shown that the obtained compounds are capable of chelating with rare earth metals, including La(III) ions. All the La(III) complexes have distorted three coordinated ligands according to MALDI MS spectral data. The presence of three coordinated water molecules in the La(III) complexes are confirmed by thermal study such as TG and DTA data. It is shown that the dehydration of La(III) hydroxocomplexes occurs at a temperature of 120–180 °C, and a further increase in temperature to 300–400 °C leads to the destruction of organic ligands with the release of CO2 and water. According to Horowitz – Metzger method, the activation energy of the dehydration process of water molecules coordinated to a metal ion of La(L1)3⋅3H2O complex was about 64.2 kJ/mol. The optical properties have been investigated by means of UV-Vis spectroscopy measurements, demonstrating that the La(III) complexes of the ligands induces a optically more favourites behaviour compared to starting li­gands. It is shown that varying the nature of the substituents and the length of the polymethene chain in the composition of dehydroacetic acid-­based chalcones affects their optical properties. The molar extinction coefficient(ε) values of the obtained La(III) complexes were ranged from 2.4 105 L⋅mol-1⋅cm-1 to 5.5⋅105L⋅mol-1⋅cm-1, suggests a strong optical properties of thedehydroacetic acid-based chalcones complexes with La(III) ions. Further dehydroacetic acid-based chalcone modifications with a series of antenna moieties for the development of highly UV-Visible chalcones complexes are in progress to study their various optical potential.