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The effect of conjugated dinitrones N,N-dimethylglyoxaldinitrone, N,N-di-tert-butylglyoxaldinitrone, and N,N-diphenylglyoxaldinitrone on the radical polymerization of styrene initiated by azobis(isobutyronitrile) is studied. It is found that, during the polymerization of styrene at temperatures below 90°C, chains terminate on the studied nitrones to generate high molecular weight nitroxide radicals. The regularities of polystyrene synthesis in the presence of conjugated nitrones at 130°C (the first reaction order with respect to the monomer over the entire conversion range, a linear increase in molecular weight with conversion, and postpolymerization) indicate that the polymerization of styrene can be implemented under reversible inhibition conditions in the high temperature regime. It is shown that the acceptance and specific features of styrene polymerization mediated by nitroxide radicals formed in situ are directly related to the initial structure of dinitrones. For example, the presence of conjugation between phenyl and nitronyl groups in diphenyl dinitrone leads to a decrease in its accepting ability, lowering the effectiveness of high molecular weight nitroxides as polymerization regulators in the high temperature mode. Using the methods of static and dynamic light scattering, the hydrodynamic sizes of macromolecules are estimated and the form factor Rg/Rh of a linear polymer and polymers synthesized with the participation of dinitrones is calculated.

Experimental and experimental–theoretical studies (using the molecular invariom) of the electron density distribution are performed for the η6-[3-acetyltetrahydro-6-phenyl-2Н-1,3-oxazine]tricarbonylchromium(0) complex. The topological characteristics of the electron density (ρ(r), ∇2ρ(r)) at the critical points (3, –1) coincide in the experimental and experimental–theoretical distributions within the “transferability indices.” The experimental–theoretical study more reliably localizes the “expected” critical points (3, –1) between the chromium atom and arene ligand.

Charge distribution and frontier orbital energies of styrene, C,N-diphenylnitrone, and their (arene)-(tricarbonyl)chromium complexes were calculated by quantum chemical methods. The difference in the HOMO and LUMO energies of the chromium complexes was found to be smaller than in the free ligands, and the reactions with (arene)(tricarbonyl)chromium complexes were characterized by higher rate and selectivity.

A new synthetic route to trimethylgallium was developed. It is based on preparation of gallium methyl derivatives by the Green reaction, followed by their alkylation with methyl Grignard reagent. The suggested procedure is well reproducible, with the yield of pure trimethylgallium exceeding 90%.