Certain problems in the structure of tin-containing complexes of 3,6-di-tertbutyl-o-benzoquinone and metallotropic transitions in these systems

Abstract

1. For tin-containing complexes of 3,6-di-tert-butyl-o-benzoquinone, the parameters of the ESR spectra (HFI with ring protons and with117Sn and119Sn nuclei) and the distribution of spin density in the free-radical ligand depend on the nature of the substituents on the Sn atom. 2. The frequency of “stannotropic” migration in the radicals that we have investigated is determined by the strength of the Sn-O bond, the coordination unsaturation of the Sn atom, and the spin density on the univalent O atom; as these latter factors become more important, pentacoordinated structures appear, with equivalent Sn-O bonds. 3. The polarity of the medium determines the direction of the reaction of ligand substitution in the interaction of the o-quinone with organic monochlorotin compounds; in nonpolar media, the organic ligand is replaced, and in polar media (DMSO), the Cl atom is replaced.