Electron Transfer in Mixed-Valence Polyferrocenium Cations: Preparation, Electrochemistry, and 57Fe Mössbauer Characteristics

摘要: Convenient new methods are developed for the preparation of 1‘,1‘‘‘‘‘-disubstituted triferrocenes and tetraferrocenes that can be oxidized with iodine to a series mixed-valence compounds. The X-ray structures 1‘,1‘‘‘‘‘-diethyltriferrocene, 1‘,1‘‘‘‘‘-dimethoxymethyltriferrocene, 1‘,1‘‘‘‘‘-dimethoxymethyltetraferrocene have been determined at 298 K. rates intramolecular electron transfer in these cations were estimated by variable-temperature 57Fe Mossbauer experiments. features all 80 300 K spectra include two doublets, one quadrupole splitting (ΔEQ) ∼2 mm s-1 (Fe(II) site) other ΔEQ = ∼0.3 (Fe(III) site). This pattern doublets is expected biferrocenium cation valence-trapped on time scale technique (electron-transfer rate <∼107 solid state). electrochemical measurements also presented.