A New Polytopic Bis-diazacrown-ether-polypyridine Ligand and Its Complexes with Zn(II) Salts and Mononuclear and Dendritic Ru(II) Precursors. Synthesis, Absorption Spectra, Redox Behavior, and Lumines
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- 作者：Fré ; dé ; rique Loiseau ; Cinzia Di Pietro ; Scolastica Serroni ; Sebastiano Campagna ; Antonino Licciardello ; Amedea Manfredi ; Gianluca Pozzi ; and Silvio Quici
- 刊名：Inorganic Chemistry
- 出版年：2001
- 出版时间：December 31, 2001
- 年：2001
- 卷：40
- 期：27
- 页码：6901 - 6909
- 全文大小：124K
- 年卷期：v.40,no.27(December 31, 2001)
- ISSN：1520-510X
文摘
The new polytopic receptor 1 containing two terpyridine, one phenanthroline, and two diazacrown-ether sites hasbeen prepared using a modular approach. Such a new species contains several pieces of information in its structurewhich can be processed by different metal ions to give different supramolecular inorganic architectures. Actually,reaction of 1 with Zn(CH3COO)2 in methanol, and subsequent anion exchange, afforded the intramolecular ring-type [Zn(1)]2+ complex, which appears to be formed by a self-assembling reaction. A different synthetic approach,stepwise synthesis, allowed us to synthesize the two multicomponent compounds [(bpy)2Ru(
-1)Ru(bpy)2]4+ (Ru2;bpy = 2,2'-bipyridine) and [{(bpy)2Ru(-2,3-dpp)}2Ru(-1)Ru{(-2,3-dpp)Ru(bpy)2}2]12+ (Ru6; 2,3-dpp = 2,3-bis(2-pyridyl)pyrazine). The absorption spectra and luminescence properties of 1 and [Zn(1)]2+ are dominated by
* transitions and excited states. The absorption spectra of the ruthenium compounds are dominated byligand-centered (LC) bands in the UV region and metal-to-ligand charge-transfer (MLCT) bands in the visible.The latter compounds undergo several reversible metal-centered oxidations and ligand-centered reductions in thepotential window investigated (-2.0/+2.0 V versus SCE) and exhibit MLCT luminescence in both acetonitrilefluid solution at room temperature and in butyronitrile rigid matrix at 77 K. Both the redox and photophysicalproperties of Ru2 and Ru6 can be assigned to specific subunits of the multicomponent structures. The data indicatethat the {Ru(bpy)2}2+ and the dendritic {Ru[(-2,3-dpp)Ru(bpy)2]2}6+ fragments appended to the polytopic 1ligands behave as independent components of the multicomponent arrays.
-1)Ru(bpy)2]4+ (Ru2;bpy = 2,2'-bipyridine) and [{(bpy)2Ru(-2,3-dpp)}2Ru(-1)Ru{(-2,3-dpp)Ru(bpy)2}2]12+ (Ru6; 2,3-dpp = 2,3-bis(2-pyridyl)pyrazine). The absorption spectra and luminescence properties of 1 and [Zn(1)]2+ are dominated by * transitions and excited states. The absorption spectra of the ruthenium compounds are dominated byligand-centered (LC) bands in the UV region and metal-to-ligand charge-transfer (MLCT) bands in the visible.The latter compounds undergo several reversible metal-centered oxidations and ligand-centered reductions in thepotential window investigated (-2.0/+2.0 V versus SCE) and exhibit MLCT luminescence in both acetonitrilefluid solution at room temperature and in butyronitrile rigid matrix at 77 K. Both the redox and photophysicalproperties of Ru2 and Ru6 can be assigned to specific subunits of the multicomponent structures. The data indicatethat the {Ru(bpy)2}2+ and the dendritic {Ru[(-2,3-dpp)Ru(bpy)2]2}6+ fragments appended to the polytopic 1ligands behave as independent components of the multicomponent arrays.