title: Anion binding of short, flexible aryl triazole oligomers.
abstract: The flexible, electropositive cavity of linear 1,4-diaryl-1,2,3-triazole oligomers provides a suitable host for complexation of various anions. The binding affinities for various combinations of oligomer and anion were determined by (1)H NMR titrations. Effective ionic radius is found to be a primary determinant of the relative binding interactions of various guests, with small but measurable deviations in the case of nonspherical anions. Solvent effects are significant, and the strength of the binding interaction is found to depend directly on the donor ability of the solvent. A picture emerges in which anion binding can be effectively interpreted in terms of a competition between two solvation spheres: one provided by the solvent and a second dominated by a folded cavity lined with electropositive 1,2,3-triazole CH protons. Implications for rigid macrocycles and other multivalent hosts are discussed.
authors.affiliation: Department of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708, USA.
authors.forename: Hemraj
authors.initials: H
authors.lastname: Juwarker
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Lenhardt
authors.forename: José C
authors.initials: JC
authors.lastname: Castillo
authors.forename: Emily
authors.initials: E
authors.lastname: Zhao
authors.forename: Sibi
authors.initials: S
authors.lastname: Krishnamurthy
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Jamiolkowski
authors.forename: Ki-Hyon
authors.initials: KH
authors.lastname: Kim
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Craig
mesh_terms: D000838:Anions / Q000737:chemistry*; D001665:Binding Sites; D047028:Macrocyclic Compounds; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D011108:Polymers / Q000737:chemistry*; D012997:Solvents; D014230:Triazoles / Q000737:chemistry*
chemical_list: D000838:Anions; D047028:Macrocyclic Compounds; D011108:Polymers; D012997:Solvents; D014230:Triazoles