Syntheses and Characterizations of Cyanido-bridged Dinuclear Ru-complexes and Their MMCT Properties in the One-electron Oxidation State

We have designed and synthesized a family of dinuclear cyanido-bridged complexes[PY5Me2Ru(μ-CN)Ru(dppe)CpMen][PF6]2(PY5Me2=2,6-bis (1,1-bis(2-pyridyl)ethyl) pyridine,Cp=cyclopentadienyl,n=0,2[PF6]2;n=1,3[PF6]2;n=5,4[PF6]2) by using a mononuclear complex[PY5Me2Ru(μ-CN)][PF6](1) as the precursor.All the three complexes have been fully characterized by including single-crystal X-ray diffraction analysis.The one-electron oxidation complexes 23+,33+and 43+obtained in situ all show a MMCT absorption band in the visible range.The MMCT energy increases as the redox potential of the N-terminal fragments decreases,and the redox potential decreases as the number of methyl groups on the cyclopentadiene of the cyanido-nitrogen coordinated Ru metal increases,supported by the TDF/TDDFT calculations.