Proton-Driven Self-Assembled Systems Based on Cyclam-Cored Dendrimers and [Ru(bpy)(CN)4]2-
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- 作者：Giacomo Bergamini ; Christophe Saudan ; Paola Ceroni ; Mauro Maestri ; Vincenzo Balzani ; Marius Gorka ; Sang-Kyu Lee ; Jeroen van Heyst ; and Fritz Vö ; gtle
- 刊名：Journal of the American Chemical Society
- 出版年：2004
- 出版时间：December 22, 2004
- 年：2004
- 卷：126
- 期：50
- 页码：16466 - 16471
- 全文大小：144K
- 年卷期：v.126,no.50(December 22, 2004)
- ISSN：1520-5126
文摘
1,4,8,11-Tetraazacyclotetradecane (cyclam), which is one of the most extensively investigatedligands in coordination chemistry, in its protonated forms, can play the role of host toward cyanide metalcomplexes. We have investigated the acid-driven adducts formed in acetonitrile-dichloromethane (1:1v/v) solution by [Ru(bpy)(CN)4]2- with 1,4,8,11-tetrakis(naphthylmethyl)cyclam (1) and a dendrimer consistingof a cyclam core appended with 12 dimethoxybenzene and 16 naphthyl units (2). [Ru(bpy)(CN)4]2-, 1, and2 exhibit characteristic absorption and emission bands, in distinct spectral regions, that are strongly affectedby addition of acid. When a solution containing equimolar amounts of [Ru(bpy)(CN)4]2- and 1 or 2 is titratedby trifluoroacetic acid, or when [Ru(bpy)(CN)4]2- is titrated with (1·2H)2+ or (2·2H)2+, {[Ru(bpy)(CN)4]2-·(2H+)·1}or {[Ru(bpy)(CN)4]2-·(2H+)·2} adducts are formed in which the fluorescence of the naphthyl units is stronglyquenched by very efficient energy transfer to the metal complex, as shown by the sensitized luminescenceof the latter. The {[Ru(bpy)(CN)4]2-·(2H+)·1} and {[Ru(bpy)(CN)4]2-·(2H+)·2} adducts can be disrupted (i)by addition of a base (1,4-diazabicyclo[2.2.2]octane), yielding the starting species [Ru(bpy)(CN)4]2- and 1or 2, or (ii) by further addition of triflic acid, with formation of (1·2H)2+ or (2·2H)2+ and protonated forms of[Ru(bpy)(CN)4]2-. It is shown that upon stimulation with two chemical inputs (acid and base) both{[Ru(bpy)(CN)4]2-·(2H+)·1} and {[Ru(bpy)(CN)4]2-·(2H+)·2} exhibit two distinct optical outputs (a naphthalene-based and a Ru(bpy)-based emission) that behave according to an XOR and an XNOR logic, respectively.