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Published on: April 19, 2019
Highly effective binding of methyl viologen dication and its radical cation by p-sulfonatocalix[4,5]arenes
Dong-Sheng Guo1, Li-Hua Wang, Yu Liu
1Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, People's Republic of China.
Abstract:
The binding behaviors and thermodynamic origins of p-sulfonatocalix[4]arene (C4AS) and p-sulfonatocalix[5]arene (C5AS) with methyl viologen (MV2+) have been investigated by the methods of isothermal titration calorimetry, NMR, and cyclic voltammetry, showing that the binding abilities of C4AS and C5AS and their host selectivity are dramatically pH-controlled, which is closely discussed from the viewpoint of thermodynamics. Moreover, the radical form of MV+* can also be effectively included by C4AS and C5AS.
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