@article{Mishchenko_Trunova_Makotryk_2021, title={THERMODESTRUCTION OF Lа(III) COORDINATION COMPOUNDS WITH ALIPHATIC β-KETO­ESTERS}, volume={87}, url={https://ucj.org.ua/index.php/journal/article/view/343}, DOI={10.33609/2708-129X.87.08.2021.99-115}, abstractNote={<p>Mono- and mixed-ligand complexes of La&nbsp;(III) with aliphatic β-ketoesters were synthesized in the solid state. The complexes have the general formulas LаL<sub>2</sub>OH·H<sub>2</sub>O (L=meacac, etacac, alacac) and La(meacac)<sub>2</sub>X·<em>n</em>CH<sub>3</sub>OH(X = NO<sub>3</sub>, CH<sub>3</sub>COO; <em>n</em> = 1, 2). Their composition, structure, and thermal properties were established by chemical and thermal analysis,&nbsp; IR spectroscopy. It is shown that β-ketoesters are coordinated to the La (III) ion bidentate-cyclically into monoligand hydroxocomp­lexes. Ligand complexes with methylacetoacetate have an oligomeric structure. They consist of cationic fragments [La(meacac)2]+ with bridged connection of the nitrate or acetate anions.</p> <p>The thermal destructions of LaL<sub>2</sub>OH·H<sub>2</sub>O (L = meacac, etacac, alacac), La(meacac)<sub>2</sub>NO<sub>3</sub>· 2CH<sub>3</sub>OH and La(meacac)<sub>2</sub>(CH<sub>3</sub>COO)·CH<sub>3</sub>OH were studied for the first time in the helium dynamic atmosphere by TGA-MS in the temperature range of 25–900&nbsp;°C. Depending on the ligand, dehydratation of the hydroxo-complexes takes place in the 120–180 (meacac), 120–190 (etacac) or 110–160&nbsp;°C (alacac) temperature range, and the mass loss corresponds with the detachment of one water molecule. Decomposition of mixed-ligand complexes starts with the detachment of methanol in the 60–100&nbsp;°C range. For La(meacac)<sub>2</sub>NO<sub>3</sub>·2CH<sub>3</sub>OH the decomposition process is attended with oxidation of methanol to carbon dioxide due to reduction of the nitrate-ion to nitrogen dioxide. Further heating to 300–400&nbsp;°C leads to destruction of organic parts of the complexes attended with the release of low-molecular oxygen-containing organic compounds (aldehydes, ketones, alcohols), carbon dioxide and water. At ~500&nbsp;°C all the La(III) complexes under study totally decompose, yielding the oxycarbonate La<sub>2</sub>O<sub>2</sub>CO<sub>3</sub>, which was fixed by IR spectroscopy. Under further heating to 850 °С oxycarbonate gradually decomposes to La<sub>2</sub>O<sub>3</sub> liberating CO<sub>2</sub>.</p&gt;}, number={8}, journal={Ukrainian Chemistry Journal}, author={Mishchenko , Artem and Trunova , Elena and Makotryk , Tamara}, year={2021}, month={Sep.}, pages={99-115} }