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Updated: Apr 20, 2026

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Linear free energy relationships reveal structural changes in hydrogen-bonded host-guest interactions
Jacqueline M McGrath1, Michael D Pluth
1Department of Chemistry and Biochemistry, Materials Science Institute, University of Oregon , Eugene, Oregon 97403-1253, United States.
Abstract:
Hydrogen bond strength in host-guest systems is modulated by many factors including preorganization, steric effects, and electronic effects. To investigate how electronic effects impact barbiturate binding in bifurcated Hamilton receptors, a library of receptors with differing electronic substituents was synthesized and (1)H NMR titrations were performed with diethyl barbital. The Hammett plot revealed a clear break between the different electronic substituents suggesting a change in binding conformation. The titration data were complimented with computational studies confirming the change in structure.
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