Complexation of Zn(II) and Cu(II) by Perfluorinated β-Diketones: Theoretical and Experimental Approaches and Potential Use as Copper-Eliminating Agents

Revision and Analysis of the Formation Constants of Rare Earth Diketonates

“…This trend is especially pronounced for metals with 4f shells (La–Lu). Indeed, for transition metals with close shell, the difference between O–CF 3 , S–CF 3 , Se–CF 3 , and Te–CF 3 is lacking (see ref and the discussion in section ). Since diketone complexes are significantly π-delocalized systems, perhaps there is an interaction between the electron pair of the chalcogen atom and 4f subshell of trivalent lanthanides.…”

“…If Coulomb interaction were the only force that exists in the metal-diketone system, the formation constant of Zn­(II) would be close to log K for gadolinium and europium. However, the Zn­(II)–diketones interaction is different …”

“…Spectral data were previously published in the series of works − listed in the corresponding Supporting Information. Each metal–ligand system has been studied in water media (concentration of ethanol does not exceed 2%) under the excess metal ions ( C M ≫ C L , of 10 times or more) at a constant concentration of ligand (molar series method).…”

“…However, the Zn(II)−diketones interaction is different. 23 Table 2 gives an overview of cumulative stability constants for Zn(II) and Eu(III) in equivalent conditions. For other diketones and Gd(III) a similar picture is observed: the difference in logβ is increased in order O−CF 3 < S−CF 3 < Se−CF 3 ≈ Te−CF 3 .…”

“…This property makes it possible to measure the chelation process between REMs and diketones using optical spectrophotometric apparatuses and determine spectral as well as thermodynamic parameters. Using this opportunity, our research team has studied several β-diketones, − some of which have been obtained for the first time. , All of these ligands can be divided into two groups: diketones with a five-membered chalcogen ring and ones with a substituted phenyl moiety (Figure ). A total of 170 conditional stability constants were determined and over 1100 single spectra of the complex species were recorded.…”