Ratiometric and Selective Fluorescent Sensor for Zn2+ as an 鈥淥ff鈥揙n鈥揙ff鈥?Switch and Logic Gate

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• 作者：Ya-Ping Li ; Hua-Rong Yang ; Qiang Zhao ; Wei-Chao Song ; Jie Han ; Xian-He Bu
• 刊名：Inorganic Chemistry
• 出版年：2012
• 出版时间：September 17, 2012
• 年：2012
• 卷：51
• 期：18
• 页码：9642-9648
• 全文大小：442K
• 年卷期：v.51,no.18(September 17, 2012)
• ISSN：1520-510X

文摘

A new chemosensor, 2,3,15,16-tetrakis(pyridin-2-yl)-7,8,10,11,20,21,23,24-octahydro[1,4,7,10,13,16]hexaoxacyclooctadecino[2,3-g:11,12-g鈥瞉diquinoxaline (1), containing 2,3-bis(pyridin-2-yl)quinoxaline and crown ether moieties, has been designed and found to be a ratiometric and selective fluorescent detector of Zn²⁺ over a wide range of tested metal ions. The addition of Zn²⁺ to the solution of 1 in acetonitrile induced the formation of a 1:2 ligand鈥搈etal complex, 1-Zn²⁺, which exhibits a remarkable enhanced fluorescent emission centered at 460 nm, with the disappearance of the fluorescent emission of 1 centered at 396 nm due to the mechanism of internal charge transfer. In contrast, the presence of K⁺ results in the fluorescence quenching of 1 and 1-Zn²⁺ through the photoinduced electron-transfer mechanism. These results demonstrate that 1 can perform as not only an INHIBIT logic gate but also an 鈥渙ff鈥搊n鈥搊ff鈥?molecular switch triggered by Zn²⁺ and K⁺. The structure of complex 1-Zn²⁺ has been characterized by single-crystal X-ray crystallography, mass spectrometry, and ¹H NMR titration experiments. Density functional theory calculation results on 1 and the 1-Zn²⁺ complex are well consistent with the experimental results.