Electrochemical synthesis of neutral divalent transition-metal complexes with tetradentate thioether–benzimidazole-containing ligands

Abstract

The electrochemical synthesis and physicochemical properties of neutral divalent transition-metal complexes [ML][H₂L = 1,7-bis(2-benzimidazolyl)-2,6-dithiaheptane or 1,6-bis(2-benzimidazolyl)-2,5-dithiahexane] of tetradentate N₂S₂ donor ligands are presented. The dianionic ligands act as tetradentate ligands with both thioether sulphurs and both deprotonated benzimidazole nitrogens co-ordinating. All compounds are four-co-ordinated in tetrahedral or distorted tetragonal geometries with the exception of the nickel complexes, in which magnetic interactions are operating, indicating that they are polymeric with a distorted-octahedral geometry around the metal.