title: Highly effective binding of methyl viologen dication and its radical cation by p-sulfonatocalix[4,5]arenes.
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.
authors.affiliation: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, People's Republic of China.
authors.forename: Dong-Sheng
authors.initials: DS
authors.lastname: Guo
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Wang
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
mesh_terms: D047250:Calixarenes / Q000737:chemistry*; D002412:Cations / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D010269:Paraquat / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*