Bimetallic ruthenium complexes bridged by divinylphenylene bearing oligo(ethylene glycol)methylether: synthesis, (spectro)electrochemistry and the lithium cation effect.
A series of 1,4-disubstituted ruthenium-vinyl complexes, (E,E)-[{(PMe3)3(CO)ClRu}2(μ-HC=CH-Ar-CH=CH)], in which the 1,4-diethenylphenylene bridge bears two oligo(ethylene glycol)methyl ether side chains at different positions (2,5- and 2,3-positions), were prepared. The respective products were characterized by elemental analyses and NMR spectroscopy. The structures of complexes 1b and 1e were established by X-ray crystallography. The electronic properties of the complexes were investigated by cyclic voltammetry, and IR and UV-vis/NIR spectroscopies. Electrochemical studies showed that the 2,5-substituents better stabilized the mixed-valence states; the electrochemical behavior was greatly affected by lithium cations, especially complex 1g with 2,3-substituents, which was further supported by IR and UV-vis/NIR spectra changes. Spectroelectrochemical studies showed that the redox chemistry was dominated by the non-innocent character of the bridging fragment.
College of Chemistry and Chemical Enginering, Yunnan Normal University, Kunming 650500, P.R. China. chxhwu@sina.com fwf@mail.ipc.ac.cn.
Li Yan
LY
Tian
Yuan Mei
YM
Liu
Guang-Xuan
GX
Tian
Xiang Hua
XH
Wu
Zhen
Z
Li
Jun-Feng
JF
Kou
Ya-Ping
YP
Ou
Sheng Hua
SH
Liu
Wen-Fu
WF
Fu