Spectroscopic and electrochemical studies of tin(iv) complexes with noninnocent N2S2 and N2O2 ligands based on acenaphthene

Abstract

New mononuclear tin(IV) complexes were obtained via condensation of tin oxides (Ph₂SnO and Et₂SnO) with acenaphthene-based bis(thiosemicarbazones). The structure of the complexes was confirmed using ¹H, ¹³C and ¹¹⁹Sn NMR spectroscopy, as well as by X-ray diffraction analysis. The electronic and redox properties of complexes 1–5 were studied using UV spectroscopy and cyclic voltammetry (CV). It was shown that the electrochemical reduction of complexes 1–5 is quasi-reversible. Radical anion derivatives of complexes were described using CV and ESR spectroscopy. The second wave of electrochemical reduction of 1–4 is accompanied by further chemical transformations, while the electroreduction of complex 5 leads to the formation of persistent dianion species.