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Updated: Jan 10, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
A Competing Hydrogen Bond Network Offers Access to a New Conformation in 24-Atom Triazine Macrocycles
K Harsha Vardan Reddy1, Arshad Mehmood2, Akop Yepremyan1
1Department of Chemistry & Biochemistry, Texas Christian University, Fort Worth, TX 76129, USA.
None:
For a family of 24-atom triazine macrocycles, a single intramolecular hydrogen bond (IMHB) network leads to a conserved, hinge-like motif in solution. Modifications to the backbone of these macrocycles preserve this motif. Modifications to peripheral sites lead to conformational isomers due to hindered bond rotation while conserving the hinge motif. Here, a competitive IMHB network is introduced by the addition of a hydrogen bond donor on the periphery. Cyclization remains quantitative, but multiple conformers result. Three conformers are derived from the hinge motif. Three others are attributed to a new motif that utilizes the new IMHB network. Crystallographic analysis confirms this hypothesis and establishes that this new motif differs significantly from the original with respect to overall shape and disposition of groups. Variable temperature 1H NMR spectroscopy is used to partially assign the spectra because conformers adopting the hinge motif undergo dynamic motion on the NMR timescale, while the new motif appears static. QTAIM analysis corroborates the hydrogen bond designations in the new conformer and categorizes these interactions as moderate and strong.
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