Heptacoordinated tin complexes with pentadentate redox-active ligands containing the diiminopyridine fragment combined with two sterically hindered phenolate coordination centers, LSn-Cl2 and L'SnCl2 (L and L' are dianions of deprotonated 2,6-bis[2,4-di-tert-butyl-6-(methylidenylamino) phenol]pyridine and 2,6-bis[2,4-di-tert-butyl-6-(ethylidenylamino)phenol]pyridine, respectively), are synthesized. The molecular and electronic structures of the synthesized compounds were studied by X-ray diffraction analysis (for complex I, CIF file CCDC no. 1557838), a set of spectral methods, and quantum-chemical calculations. The redox properties of the obtained complexes are characterized by cyclic voltammetry.

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.

The kinetics of tin oxidation with 3,6-di- tert -butyl- o -benzoquinone (3,6-Q) in toluene was studied. The scheme of formation of tin o -quinone complexes during metal oxidation with 3,6-Q in different aprotic solvents was suggested on the basis of the kinetic, EPR, and IR data.