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Specific features of the synthesis and structures of the complexes of Group 14 elements (Si, Ge, Sn, Pb) with o-iminoquinone ligands are discussed. The chemical reactions of the above indicated compounds accompanied by the transformation of the redox-active ligand in the coordination sphere of the complex- forming agent are considered. [ABSTRACT FROM AUTHOR]

New regulators of radical polymerization of methyl methacrylate based on N-(aryl)- o-iminoquinones of various structures are proposed. It is shown that samples of polymethylmethacrylate with the participation of N-(aryl)- o-iminobenzoquinones could be used as macroinitiators of polymerization. Optimal conditions to synthesize polymers in the presence of o-iminobenzoquinones are determined, which make it possible to obtain polymethylmethacrylate with a polydispersity coefficient of no more than 1.5 on deep conversions during bulk polymerization. [ABSTRACT FROM AUTHOR]

A reaction of tin(IV) bis- o-amidophenolate complex based on redox-active 4,6-di- tert-butyl- N-(2,6-diisopropylphenyl)- o-aminophenol with various allyl halides was studied. This process includes the addition of 1 equiv. of allyl halide to the starting complex and is accompanied by the change in the redox state of one of the redox-active ligands. The reaction results in the formation of a new carbon-carbon bond between the allylic fragment and the carbon atom at position 5 of the ligand o-iminoquinone ring, as well as a tin-halogen bond. The structure and composition of compounds synthesized were confirmed by ESR, NMR, and IR spectroscopy and elemental analysis. [ABSTRACT FROM AUTHOR]

Characteristic features of synthesis of various polymers with participation of the tin complex imSQSnBuCl, where imSQ is the 4,6-di- tert-butyl- N-(2,6-diisopropylphenyl)- o-iminobenzoquinone radical anion, were studied. It was shown that for a number of monomers, this complex acts as an iniferter, i.e., it can not only initiate the polymerization, but can also regulate the chain growth of macromolecules. The effect of the conditions of the process on the possibility of obtaining macromolecular products with a narrow polydispersity was estimated. [ABSTRACT FROM AUTHOR]

A family of ionic ferric catecholate complexes 1-4 bearing a disubstituted 3,6-di- tert -butyl-catecholate ligand (3,6-DBCatH 2 ) and tetradentate tris(2-pyridylmethyl)amine (TPA) was prepared and its spin transitions were investigated. Variation of the outer-sphere counteranions (PF 6 , BPh 4 , ClO 4 , BF 4 ) is accompanied by changes in the magnetic behavior of the compounds under consideration. The crystal structures of complexes 1, 3 and 4 were determined by single crystal X-ray diffraction analysis at 100 K and 293 K. The complexes were characterized by the occurrence of a thermally induced spin-crossover process in the solid state with different degrees of completeness, which was confirmed by the comprehensive spectroscopic investigation (EPR, magnetic susceptibility, Mössbauer, and XAS) of the isolated compounds. Complex 4 containing BF 4 anions was found to demonstrate valence tautomeric transition along with spin-crossover. This finding makes compound 4 the first salt-like mononuclear ferric catecholate complex exhibiting valence tautomerism.