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New chelating ligands consisting of three β-diketone fragments, viz., 1,3,5-tris[(acetylaceton-3-yl)methyl]benzene, 1,3,5-tris[(benzoylaceton-3-yl)methyl]benzene, and 1,3,5-tris[(dibenzoylmethan-1-yl)methyl]benzene, linked to each other through the mesitylene spacer were synthesized by the reaction of 1,3,5-tris(bromomethyl)benzene with the corresponding β-diketone sodium salt. The acidity of these compounds and their complexation properties were studied by pH-potentiometry in aqueous-ethanol solutions. Tris(β-diketones) form mononuclear complexes with lanthanide ions, whose stability increases in the series La3+ < Gd3+ < Lu3+. 1,3,5-Tris[(acetylaceton-3-yl)methyl]benzene forms both mononuclear and polynuclear complexes with the Ni2+ and Cu2+ ions. The stability constants and selectivity of complex formation increase substantially with an increase in the degree of deprotonation of the ligands, thus indicating that all deprotonated chelate groups are involved in coordination with the metal ion. The replacement of the methyl groups by the phenyl substituents in the β-diketone fragments of the molecules affects substantially the composition and stability of the complexes formed.

Claisen condensation of 1,3-bis(methoxycarbonylmethoxy)benzene with acetone and acetophenone afforded new chelating ligands consisting of two β-diketonate fragments, viz., 1,3-bis(acetylacetonyloxy)benzene and 1,3-bis(benzoylacetonyloxy)benzene, which are linked to each other through the resorcinol spacer. In the crystal, 1,3-bis(acetylacetonyloxy)benzene, unlike the starting ester, adopts a planar conformation and exists in the enol form. The acidities of these compounds and their complexation with lanthanide ions in aqueous ethanolic solutions were studied by pH-potentiometry. Depending on the concentration conditions and pH, the La3+, Gd3+, and Lu3+ ions form 1 : 1, 1 : 2, or 1 : 3 complexes with bis(β-diketones). The stability of the complexes increases as the atomic number of the lanthanide increases (La3+ < Gd3+ ≤ Lu3+). The complexation constants and selectivity of complexation substantially increase with increasing degree of deprotonation of the ligands, which indicates that both chelate groups of the ligands are simultaneously involved in coordination. The Ph substituents in bis(β-diketone) have a considerable effect on the composition and stability of complexes with lanthanide ions due to additional noncovalent inner-sphere interactions.

Electronic and ESR spectroscopy was used to show that the reactions of dimethylaminomethylcalix[4]resorcinarene with Cu(II) salicylaldiminates bearing alkyl substituents at the salicylaldiminate nitrogen atom give 1 : 1 adducts with the dimethylamino group coordinated axially to the Cu(II) complex. The spatially organized calix[4]resorcinarene structure and the possibility of outer-sphere interactions favor a much higher stability of the adduct compared with the similar complex with 2-dimethylaminomethylphenol. In going from alkyl to aryl substituents, salicylaldiminates are replaced by the anion derived from dimethylaminomethylcalix[4]resocinarene. The same replacement takes place in the reaction with 2-dimethylaminomethylphenol.

Solvolysis of 3,5-di-tert-butyl-4-hydroxybenzyl acetate in alcohol solutions involves intermediate formation of 2,6-di-tert-butyl-4-methylene-1-benzoquinone that further takes up a molecule of the alcohol.

Complexation of dialkylaminomethylated calix[4]resorcinarenes (H 8 X) with bis-acetylacetonates and salicylaldiminates of Cu(II) was studied by UV–VIS and EPR spectroscopy methods. The complexation was found to proceed via ternary complex formation and results in the octahedral or square–pyramidal structure with NR 2 group coordination in equatorial or axial positions of Cu(II) coordination sphere. The complexation of salicylaldiminates with N–Ar substituent is accompanied by the evaluation of salicylaldimines from the Cu(II) coordination sphere. This regularity is proposed to be determined by the structure of the initial Cu(II) complex, being square planar for Cu(II) bis-acetylacetonate and salicylaldiminates with N–Alkyl substituent and tetrahedrally distorted for salicylaldiminates with N–Ar substituent.

The reactions of tetrathiacalix[4]arene functionalised by acetylhydrazide groups with an excess of 4-nitrobenzaldehyde or tetrathiacalix[4]arene functionalised by chlorocarbonylmethoxy groups with an excess of 4-nitrobenzaldehyde hydrazone lead to the preferable formation of tetrathiacalix[4]arene with an additional N,N’ -diacetylhydrazine bridge, but in the case of pyridine-2-carboxaldehyde, only to the formation of tetrathiacalix[4]arene functionalised by four acetylhydrazone fragments.

Complex formation of 4,6-dimethyl-2-(1H)-pyrimidinone (thione) with dysprosium(III) tris(acetylacetonate), Dy(acac)3, in 80% (v/v) aqueous methanol was investigated by pH-metric titration and paramagnetic birefringence. Due to its higher basicity and lower acidity, 4,6-dimethyl-2-(1H)-pyrimidinone is coordinated by Dy(acac)3 without deprotonation, whereas its thio analog is coordinated in the deprotonated form. Due to the higher acidity of 4,6-dimethyl-2-(1H)-pyrimidinethione, the complex of its anion with Dy(acac)3 is much more stable than that derived from the oxo analog, as inferred from the comparison of the stability constants.

By reaction of 4-tert-butylphenoxyacetylhydrazide with aromatic aldehydes and acetone a new series of 4-tert-butylphenoxyacetylhydrazones was synthesized. The structural peculiarities of the investigated molecules have been determined by means of X-ray analysis and IR spectroscopy. The diagnostically important IR spectral criteria required for the conformational analysis of acethylhydrazones have been considered. It was established that the 4-tert-butylphenoxyacetylhydrazide in condensed phase exists only as a ZN–C(O)-conformer. Its derivatives exist as EN–C(O) and ZN–C(O)-forms. As a rule, the prevalence of ZN–C(O)-form has been observed in CCl4 solutions. The structure of investigated compounds is also determined by a system of inter- and intramolecular hydrogen bonds. The energy of hydrogen bonds was estimated.

A series of acyclic and macrocyclic nucleobase derivatives that contain uracil and 2-thiocytosine units linked by polymethylene spacers was prepared. The length of spacers as well as the oxidation number of sulfur atoms entering into the structure of the compounds was varied. The crystal structure of pyrimidinophane with hexa- and heptamethylene linkers was established by X-ray analysis. The metal ion-binding properties of pyrimidinophanes and their acyclic counterparts were investigated by liquid extraction and 1H NMR titration experiments. The compounds with 2-thiocytosine fragments revealed a high selectivity of extraction towards Ag+ ions. The stoichiometry of silver complexes and the binding constants have been determined. The antibacterial activity of these complexes was also discussed.

It is shown by pH-metric titration that calix[4]resorcinarenes can bind cobalt(III)-containing complex monocations in alkaline water-organic media; the binding constants depend on the complex cation structure and are independent of the charge of the calix[4]resorcinarene anion.

Some new classes of complexones based on functionalized thiacalix[4]arenes, calix[4]resorcin- and pyrogallolarenes were synthesized and their ionophore properties were studied toward alkali and some d and f metal cations. Calixarenes, unlike their noncyclic analogs, were shown to exhibit cooperataive effect of different noncovalent interactions due to preorganization of donor groups on calixarene matrix.