lanthanum complexes, β-keto­esters, thermal analysis.

How to Cite

Mishchenko , A., Trunova , E., & Makotryk , T. (2021). THERMODESTRUCTION OF Lа(III) COORDINATION COMPOUNDS WITH ALIPHATIC β-KETO­ESTERS. Ukrainian Chemistry Journal, 87(8), 99-115.


Mono- and mixed-ligand complexes of La (III) with aliphatic β-ketoesters were synthesized in the solid state. The complexes have the general formulas LаL2OH·H2O (L=meacac, etacac, alacac) and La(meacac)2nCH3OH(X = NO3, CH3COO; n = 1, 2). Their composition, structure, and thermal properties were established by chemical and thermal analysis,  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.

The thermal destructions of LaL2OH·H2O (L = meacac, etacac, alacac), La(meacac)2NO3· 2CH3OH and La(meacac)2(CH3COO)·CH3OH were studied for the first time in the helium dynamic atmosphere by TGA-MS in the temperature range of 25–900 °C. Depending on the ligand, dehydratation of the hydroxo-complexes takes place in the 120–180 (meacac), 120–190 (etacac) or 110–160 °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 °C range. For La(meacac)2NO3·2CH3OH 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 °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 °C all the La(III) complexes under study totally decompose, yielding the oxycarbonate La2O2CO3, which was fixed by IR spectroscopy. Under further heating to 850 °С oxycarbonate gradually decomposes to La2O3 liberating CO2.


Yatsimirsky K.B., Kostromina N.A., Sheka Z.A., Davidenko N.K., Kriss E.E., Ermolenko V.I. Chemistry of complex compounds of rare earth elementsю. Kiev: Naukova Dumka, 1966 (In Russian).

Poluektov N.S., Drobyazko V.N., Beltyukova S.V., Kononenko L.I. Spectrophotometric study of the complexation of neodymium (III), holmium (III) and erbium (III) ions with acetoacetic ether. Russ. Coord. Che­mistry. 1977. 3 (4): 476–479.

Beltyukova S.V., Nazarenko N.A., Krav­chenko T.B., Poluektov N.S. Correlation of the intensity of hypersensitive transitions in solutions of complexes with the polari­zability of the ligand molecule. Dokl. АN URSR. 1981. 259 (2): 139–141 (In Russian).

Devi R., Bala M., Khatkar S.P., Taxak V.B., Boora P. Investigations of luminescent behavior and intramolecular energy transfer mechanism of europium(III) complexes with fluorinated β-ketoester ligand. J. Fluorine Chem. 2016. 181: 36–44.

Dutt N.K., Rahut S. Chemistry of lantha­nons-XXIII. The formation constants of the ethyl acetoacetato complexes of rare earths. J. Inorg. Nucl. Chem. 1969, 31 (10): 3177–3179.

Dutt N.K., Rahut S. Chemistry of lantha­nons – XXVII. Rare earth complexes of ethylacetoacetate. J. Inorg. Nucl. Chem. 1970. 32 (9): 2905–2909.

Hubert-Pfalzgraf L.G., Miele-Pajot N., Pa­pier­nik R., Vaissermann J. A novel exam­ple of self-assembly in lanthanide che­mis­try: synthesis and molecular structure of [Na(EtOH)6][Y9(μ4-O)2(μ3-OH)8{μ-η2- MeC(O)CHC(O)OEt}8{η2-MeC(O)CHC(O)OEt}8]. J. Chem. Soc., Dalton Trans. 1999. 4127–4130.

Savchenko I.A., Berezhnytska A.S., Ivakha N.B., Trunova E.K. New nanosized systems based lanthanide diketonate complexes for OLEDs. In Nanocomposites, Nanophoto­nics, Nanobiotechnology, and Applications; Fesenko O., Yatsenko L., Eds. Springer International Publishing: Cham. 2015. 85–94.

Trunova E.K., Ivakha N.B., Berezhnytska O.S., Rogovtsov O.O, Savchenko I.A. Monomeric and polymeric complexes of erbium (III) with β-dicarbonyl ligands. Ukr. Khim. Journal. 2015. 81 (9): 12–19 (In Ukrainian).

Ivakha N.B., Berezhnytska O.S., Trunova E.K., Savchenko I.A., Smola S.S., Zheleznova L.I., Allyl acetoacetate complexes of Nd(III), Er(III), Yb(III) as precursors ofluminescent materials. Ukr. Khim. Journal. 2018. 84 (3): 3–12 (In Ukrainian).

Souza A.P., Almeida Paz F.A., Freire R.O., Carlos L.D., Malta O.L., Alves S. Jr., de Sa G.F. Synthesis, crystal structure, and mo­deling of a new tetramer complex of europium. J. Phys. Chem. B. 2007. 111: 9228–9238.

Souza A.P., Alves S. Jr., Malta O.L. New complexes of europium and gadolinium with 2,4,6-trichlorophenyl acetoacetate as ligand. Opt. Mater. 2011. 33 (3): 402–407.

Berezhnytska O., Savchenko I., Ivakha N., Trunova O., Rusakova N., Smola S., Rogovtsov O. Synthesis, characterization and luminescent properties of polymer complexes of Nd(III) with β-dicarbonyl li­gands. Nanoscale Research Letters. 2017. 12 (338): 1–8.

Mishchenko A.M., Trunova E.K., Berezhnytska A.S. Lanthanide complexes with allylacetoacetate in mixed waterorganic media: formation, stability and bonding. J. Solution Chem. 2015. 44: 2117–2128.

Mishchenko A.M., Trunova E.K. Nephelauxetic effect in the lanthanide complexes with methyl Acetoacetate. Spectrosc. Lett. 2016. 49: 619–625.

Mishchenko A.M., Trunova E.K. Complexation of lanthanide ions with methyl acetoacetate in water-ethanol solution. Ukr. Khim. Journal. 2017. 83 (9): 11–21 (In Russian).

Mishchenko A.M., Trunova E.K. Depen­dence of the stability of lanthanide -dicarbonyl complexes on the metal–ligand bond energy. Dopov. Nac. akad. nauk Ukr. 2019. 4: 74–80.

Milanov A.P., Seidel R.W., Barreca D., Gas­parotto A., Winter M., Feydt J., Irsen S., Becker H.-W., Devi, A. Malonate complexes of dysprosium: synthesis, characte­rization and application for LI-MOCVD of dysprosium containing thin films. Dalton Trans. 2011. 40 (1): 62–78.

Lichtenberger R., Baumann S.O., Bendo­va M., Maurer C., Schubert U. Modification of yttrium alkoxides: β-ketoeste­rate-substituted yttrium alkoxo/hydroxo/oxo clusters. Inorg. Chim. Acta. 2011. 376 (1): 463–469.

Binnemans K. Rare-earth beta-diketonates. In Handbook on the Physics and Chemistry or Rare Earth, 35; Gschneidner, K.A., Jr.; Bünzli, J.-C.G.; Pecharsky, V.K., Eds.; Elsevier North-Holland: Ams­terdam. 2005. 107–272.

Schwarzenbach G., Flashch G. Complexo­metric titration. – M.: Chemistry. 1970: 360 [In Russian].

Mishchenko A.M., Trunova E.K., Zheleznova L.I., Makotryk T.A. IR spectroscopic study of lanthanide hydroxo comp­lexes with esters of acetoacetic acid. J. Appl. Spectrosc. 2019. 86 (2): 206–212.

Bunzli J.-C.G., Moret E., Yersin J.-R. Vib­rational spectra of anhydrous lanthanum, europium, gadolinium, and dysprosium nitrates and oxonitrates. Helvet. Chim. Acta. 1978. 61: 762–771.

Klingenberg B., Vannice M.A. Influence of pretreatment on lanthanum nitrate, carbonate, and oxide powders. Chem. Mater. 1996. 8 (10): 2755–2768.

Nakamoto K. Infrared spectroscopy of in-­organic and coordination compounds. – М.: Mir.1991: 536 [In Russian].

Ribot F., Toledano P., Sanchez C. X-ray and spectroscopic investigations of the structure of yttrium acetate tetrahydrate. Inorg. Chim. Acta. 1991. 185 (2): 239–245.

Wu Y., Morton S., Kong X., Nichol G.S., Zheng Z. Hydrolytic synthesis and structural characterization of lanthanide-acetylacetonato/hydroxo cluster complexes – A systematic study. Dalton Trans. 2011. 40 (5): 1041–1046.

Rogache, A.Yu., Minacheva L.Kh., Sergienko V.S .; Kuzmina, N.Р. Synthesis and crystal structure of the heteroligand complex [La(hfa)2(μ-O2CCF3)(H2O)2]2. Russian J. Inorg. Chem. 2004. 49(12): 1955–1962 (In Russian).

Lee T.A. A Beginner’s Guide to Mass Spect­ral Interpretation; John Wiley & Sons: Chichester, 1998.

Patil K.C., Chandrashekhar G.V., George M.V., Rao C.N.R. Infrared spectra and thermal decompositions of metal acetates and dicarboxylates. Can. J. Chem. 1968. 46 (2): 257–265.

Hussein, G.A.M. Spectrothermal investigation of the decomposition course of lanthanum acetate hydrate. J. Therm. Anal. 1994. 42: 1091–1102.

Turcotte R.P., Sawyer J.O., Eyring L. Rare earth dioxymonocarbonates and their decomposition. Inorg. Chem. 1969. 8 (2): 238–246.


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