Chow Cheuk-Fai, Lam Michael H W, Wong Wai-Yeung
Department of Biology & Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China.
Inorg Chem. 2004 Dec 27;43(26):8387-93. doi: 10.1021/ic0492587.
A trinuclear heterobimetallic Ru(II)-Cu(II) donor-acceptor complex, Ru(II)((t)Bubpy)(CN)(4)-Cu(II)(dien)(2) ((t)Bubpy = 4,4'-di-tert-butyl-2,2'-bipyridine; dien = diethylenetriamine) (1), has been synthesized and successfully used as an chemodosimetric ensemble for the specific detection of cyanide in aqueous DMF. X-ray crystallography, solid and solution IR spectroscopy, and conductivity measurements reveal that complex 1 is a one-dimensional polymer in the crystalline state and dissociates into its Ru(II)((t)Bubpy)(CN)(2)(CN)Cu(II)(dien)L (L = solvent) monomeric units in polar solvents. The MLCT transition and luminescence properties of the solvatochromic Ru(II)((t)Bubpy)(CN)(4)(-) donor are perturbed by the coordination of two Cu(II) acceptors but restored in the presence of CN(-). Spectroscopic and mass spectrometric studies confirm the cleavage of the cyano bridge between Ru(II) and Cu(II) of the chemodosimetric ensemble after the binding of cyanide to the Cu(II) centers. The overall binding constant, K(B), between 1 and CN(-) is measured to be (7.39 +/- 0.23) x 10(6) M(-2). A detection limit of 1.2 microM (0.03 ppm) of CN(-) in aqueous DMF (pH 7.4) is achievable. Thermodynamic evaluation shows that the analyte specificity of chemodosimeter 1 is attributable to the relative stability of the donor-acceptor complex to that of adducts formed between the acceptor metal center and the analytes.
一种三核异双金属钌（II）-铜（II）供体-受体配合物，Ru(II)((t)Bubpy)(CN)(4)-Cu(II)(dien)(2) （(t)Bubpy = 4,4'-二叔丁基-2,2'-联吡啶；dien = 二乙烯三胺）（1），已被合成并成功用作化学计量检测体系，用于在水-DMF中特异性检测氰化物。X射线晶体学、固体和溶液红外光谱以及电导率测量表明，配合物1在晶体状态下是一维聚合物，在极性溶剂中解离成其Ru(II)((t)Bubpy)(CN)(2)(CN)Cu(II)(dien)L （L = 溶剂）单体单元。溶剂致变色的Ru(II)((t)Bubpy)(CN)(4)(-)供体的MLCT跃迁和发光性质受到两个铜（II）受体配位的干扰，但在有CN(-)存在时恢复。光谱和质谱研究证实，在氰化物与铜（II）中心结合后，化学计量检测体系中钌（II）和铜（II）之间的氰基桥发生断裂。测得1与CN(-)之间的总结合常数K(B)为(7.39 ± 0.23) x 10(6) M(-2)。在水-DMF（pH 7.4）中可实现对CN(-)的检测限为1.2 μM（0.03 ppm）。热力学评估表明，化学计量计1的分析物特异性归因于供体-受体配合物相对于受体金属中心与分析物形成的加合物的相对稳定性。
