Ruthenium(II) Coordination Chemistry of a Fused Donor−Acceptor Ligand: Synthesis, Characterization, and Photoinduced Electron-Transfer Reactions of [{Ru(bpy)2}n(TTF-
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- 作者：Christine Goze ; Nathalie Dupont ; Elvira Beitler ; Claudia Leiggener ; Hongpeng Jia ; Philippe Monbaron ; Shi-Xia Liu ; Antonia Neels ; Andreas Hauser ; Silvio Decurtins
- 刊名：Inorganic Chemistry
- 出版年：2008
- 出版时间：December 1, 2008
- 年：2008
- 卷：47
- 期：23
- 页码：11010-11017
- 全文大小：330K
- 年卷期：v.47,no.23(December 1, 2008)
- ISSN：1520-510X
文摘
A π-extended, redox-active bridging ligand 4′,5′-bis(propylthio)tetrathiafulvenyl[i]dipyrido[2,3-a:3′,2′-c]phenazine (L) was prepared via direct Schiff-base condensation of the corresponding diamine−tetrathiafulvalene (TTF) precursor with 4,7-phenanthroline-5,6-dione. Reactions of L with [Ru(bpy)2Cl2] afforded its stable mono- and dinuclear ruthenium(II) complexes 1 and 2. They have been fully characterized, and their photophysical and electrochemical properties are reported together with those of [Ru(bpy)2(ppb)]2+ and [Ru(bpy)2(μ-ppb)Ru(bpy)2]4+ (ppb = dipyrido[2,3-a:3′,2′-c]phenazine) for comparison. In all cases, the first excited state corresponds to an intramolecular TTF → ppb charge-transfer state. Both ruthenium(II) complexes show two strong and well-separated metal-to-ligand charge-transfer (MLCT) absorption bands, whereas the 3MLCT luminescence is strongly quenched via electron transfer from the TTF subunit. Clearly, the transient absorption spectra illustrate the role of the TTF fragment as an electron donor, which induces a triplet intraligand charge-transfer state (3ILCT) with lifetimes of approximately 200 and 50 ns for mono- and dinuclear ruthenium(II) complexes, respectively.