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Reactions of [{Re6Q8}Br6]4−/3− (Q = S, Se) with molten imidazole lead to the formation of two new neutral cluster complexes [{Re6Q8}(imzH)4(imz)2] (imzH = imidazole). The interaction of [{Re6Q8}(imzH)4(imz)2] with hydrohalic acids resulted in cationic complexes [{Re6Q8}(imzH)6]X2 (X = Cl, Br). All compounds were characterised by X-ray single-crystal and powder diffraction analyses, elemental analysis, energy dispersive X-ray and IR spectroscopies. The luminescence of the neutral compounds [{Re6Q8}(imzH)4(imz)2] was also studied.

(Bu4N)2[Mo6I8(N3)6] undergoes [3+2] cycloaddition with benzonitrile or 2,3,4,5,6-pentafluorobenzonitrile in the presence of I2 catalyst with the formation of novel hexakis(tetrazolate)complexes, (Bu4N)2[Mo6I8(N4C-Ar)6] (Ar = C6H5 (1), C6F5 (2)) with coordinated 2,5-tetrazolyl ligands. The products were characterized by X-ray analysis, NMR, IR and ESI-mass spectrometry. The complexes undergo quasi reversible oxidation and are red-light emissive upon UV photoexcitation.

The coordination compounds of Cu(II), Co(II), Ni(II) and Pd(II) with 2-anilinomethylidene-5,5-dimethylcyclohexane-1,3-dione (HL) of the composition [ML2(C2H5OH)2]·nH2O (M = Co (n = 1), Ni (n = 0)) and [ML2] (M = Cu, Pd) have been prepared and investigated by elemental analysis, IR-spectroscopy, NMR spectroscopy, powder X-ray diffraction analysis. Single-crystal X-ray diffraction analysis shows that HL serves as a chelate bidentate ligand coordinated to the metal ion through the N and O atoms forming a six-membered chelate ring. The coordination polyhedron of the metal atoms is a square bipyramid [ML2(C2H5OH)2] or square planar [ML2]. The Cu(II) and Pd(II) complexes stability in solution has been shown by NMR spectroscopy. The results of the cell viability study on Hep2 (human larynx carcinoma) cells demonstrate that the complexes don’t exhibit strong cytotoxic effect against Hep-2 cell line compared to cisplatin (IC50 = 9,2 ± 0,5 μM). Palladium(II) complex is the most cytotoxic among all complexes and shows IC50 value of 68,7 ± 5,3 μM.

The dichlorine-containing tris-dioximate iron(II) clathrochelate undergoes a radical addition–elimination reaction with the radical derivatives of 1,4-dioxane to yield ribbed-functionalized C-alkylated macrobicyclic complexes. The clathrochelates obtained have been characterized using elemental analysis, MALDI-TOF mass, IR, UV–Vis and multinuclear NMR spectra, as well as X-ray crystallography. This unexpected and previously unknown radical reaction is a novel approach to the ribbed functionalization of tris-dioximate d-metal clathrochelates, and it can be extended to other cyclic ethers.

Methods for the synthesis of a new family of nitronylnitroxides, iminonitroxides, and their precursors with 2-hydroxyphenyl or 3-hydroxypyridin-2-yl substituents in the side chain have been developed. Five heterospin chelates of Cu(II) with deprotonated iminonitroxides have been isolated. Their structure and magnetic properties have been studied. In all complexes, ferromagnetic intramolecular exchange interactions take place (J∼40–350 cm−1).