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Radical polymerization of methyl methacrylate was studied in the presence of initiating systems based on bis[4,6-di-tert-butyl-N-(2,6-dimethylphenyl)-o-iminobenzosemiquinono]-cobalt(II) and hydrocarbon halo derivatives of different structure. The introduction of amines in the polymerizing system was found to lead to a significant increase in the polymerization rate. The polymerization proceeds via the atom transfer mechanism, which was confirmed by detection of ω-terminal chlorine atoms in the macromolecules by NMR, the linear dependence of the polymer molecular weight on conversion of monomer, and the synthesis of block-copolymers.

The complex of triphenylantimony(V) 3,6-di-tert-butylcatecholate with 5-(2,6-dimethylphenyl)-3-(4-pyridyl)-1-phenylformazan was synthesized and characterized by spectroscopic and electrochemical methods and by X-ray diffraction. In the crystal structure, there are intermolecular hydrogen bonds between the formazan ligands of adjacent molecules. The electrochemical transformations of the complex were investigated by cyclic voltammetry. It was shown that both the formazan and catecholate moieties are involved in redox processes.

The reactions of triphenylantimony(V) catecholates (Cat)SbPh3 with different tetraalkyl-ammonium salts (bromides, iodides, hydroxide anions) in acetonitrile were investigated, and their complexes 8–13 of the general formula [R4N]+[(Cat)SbPh3X]− were synthesized. The molecular structure of complex 8 was determined by X-ray diffraction. The electrochemical oxidation of complexes 8–13 proceeds more easily than the oxidation of the starting catecholates (Cat)SbPh3. The coordination of the bromide anion results in the stabilization of the oxidized forms of the complexes [(SQ)SbPh3X]0 and [(Q)SbPh3X]+ (SQ and Q are the o-benzosemiquinone and o-benzoquinone forms of the redox-active ligand, respectively).

Cyclization of substituted quinone imines and diazabutadiene derivatives of aminophenols affords 4aH-phenoxazine or 4H-1,4-benzoxazine derivatives, which are finally transformed into the following fused heterocycles: the stable 1,4,6,8-tetra(tert-butyl)phenoxazin-10-yl radical and 7a,14a,15a, 15b-tetrahydro-14,16-dioxa-5,9-diaza-8,15-ethenohexaphene and 5a,6,11a, 12-tetrahydro[1,4]benzoxazino[3,2-b][1,4]benzoxazine derivatives. The influence of the substituents on the pathways of the reactions of intermediate benzoxazines and phenoxazines, such as oxidation, [2+4] dimerization, and the closure of the second ring, was studied. The structures of the fused heterocycles were determined by X-ray diffraction, NMR spectroscopy, and ESR.