The Features of Interaction of Bis(4, 6-di-tert-butyl-N-(2, 6-diisopropylphenyl)-o-amidophenolato)tin(IV) with Bromine and Iodine

The oxidation of tin(IV) bis-amidophenolate (APiPr)2Sn.THF (I) by bromine and iodine leads to the formation of monoradical mixed-ligand complexes (APiPr)(ISQiPr)SnBr.THF (II) and (APiPr)(ISQiPr)SnI.THF (III) or diradical complexes (ISQiPr)2SnBr2 (IV) and (ISQiPr)2SnI2 (V), respectively [APiPr = dianion 4, 6-di-tert-butyl-N-(2, 6-diisopropylphenyl)-o-amidophenolate; ISQiPr = radical-anion 4, 6-di-tert-butyl-N-(2, 6-diisopropylphenyl)-o-iminobenzosemiquinone], depending on the molar ratio of reagents (2:1 or 1:1). According to EPR data for compounds II and III, the unpaired electron is delocalized between both organic ligands. The EPR spectrum of IV in toluene matrix at 130 K is typical for diradical species with S = 1 with parameters D = 530 G, E = 105 G. The mixed-ligand complexes II and III are unstable and undergo to symmetrization leading to formation of IV or V. The molecular structures of IV and V are determined by X-ray analysis.