Abstrakt: |
The cyanide-bridged compounds trans-[Cp(dppe)FeII(NC)RuII(py)4(CN)FeII(dppe)Cp][PF6]2 (1, py = pyridine, dppe = bis (diphenylphosphino) ethane, Cp = cyclopentadienyl anion), trans-[Cp(dppe)FeII(NC)RuII(py)4(CN)FeIII(dppe)Cp][PF6]3 (2), trans-[Cp(dppe)FeIII(NC)RuII(py)4(CN)FeIII(dppe)Cp][PF6]4 (3), trans-[Cp(dppe)FeII(NC)RuII(MeOpy)4(CN)FeII(dppe)Cp][PF6]2 (4, MeOpy = 4-methoxypyridine) and trans-[Cp(dppe)FeIII(NC)RuII(MeOpy)4(CN)FeII(dppe)Cp][PF6]3 (5) were systematically synthesized and characterized by IR spectroscopy, electronic absorption spectroscopy, elemental analysis, mass spectrometry and cyclic voltammetry. Fortunately, crystals of 1, 2, 4, trans-RuII(MeOpy)4(CN)2 and [CpFeIII(dppe)Br](PF6) suitable for single-crystal X-ray diffraction analysis were obtained. The metal-to-metal charge transfer (MMCT) of the one-electron oxidation products 2 and 5 is mainly attributed to the RuII and FeII to FeIII MMCT transitions, and the MMCT of the two-electron oxidation product 3 is mainly attributed to the RuII→FeIII MMCT transitions. According to the classification of Robin and Day, compounds 2, 3 and 5 belong to the class II mixed-valence compounds. The IR spectra, MMCT band and redox splitting of compounds 2 and 5 indicate that replacing the py ligand in the central unit with MeOpy shows better electronic communication properties. [ABSTRACT FROM AUTHOR] |