Linkage Isomers of Ruthenium Alizarin Complexes
Linkage Isomers of Ruthenium Alizarin Complexes
复制标题
钌茜素配合物的键合异构体
DOI：
10.1021/ic00086a003
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
W. Pietro
中科院分区：
文献类型：
--
作者：
A. DelMedico;P. Auburn;E. S. Dodsworth;A. Lever;W. Pietro
For molecular switch and/or information storage systems, molecules are required which can exist in two stable forms and be conveniently interconverted. Most systems reported to date involve complex organic systems and cis/trans isomerism or cyclization. 1-7 We report here an inorganic system involving linkage isomers of an alizarin-bis (bipyridine) ruthenium (II) complex1 2345678· 9 [isomers QCat^ Ru-l,!) and QCat^(Ru-l, 9) as shown in Figure 1], with significantly different electronic spectra (Figure 2). Comparison with the 1-hydroxyanthraquinone (QOH) bis-(bipyridine) ruthenium complex [QO~(Ru-l, 9)] n aids in the elucidation of the bonding of these isomers. Alizarin (1, 2-dihydroxy-9, 10-anthraquinone) contains two redox-active quinonoid fragments, the 9, 10-dioxo unit labeled here as pQ, p-Sq, or p-HQ2-in its neutral quinone, one electron reduced (-1), and two electron reduced (-2) redox levels, and the 1, 2-catechol-like fragment labeled oQ, o-Sq, and o-Cat in its quinone, semiquinone, and catechol forms. Alizarin will be abbreviated as QCatHz, Q referring to the 9, 10-dioxo unit and CatH2 referring to the doubly protonated 1, 2-catechol unit. The abbreviations used include (Ru-1, 2) or (Ru-1, 9) to indicate the site of ruthenium coordination.Protonation of QCat^ CRu-LZ) gives QCatH~(Ru-l, 9), as followed by electronic spectroscopy (Figure 1). Deprotonation of QCatH~(Ru-l, 9) gives QCat2_ (Ru-l, 9), which is reversibly interconverted to QCatH~(Ru-l, 9) by additionof acid. 13 Most importantly, complex QCat1-(Ru-l, 9) converts back to complex
