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Title: Cucurbit[8]uril forms tight inclusion complexes with cationic triamantanes
We report the synthesis of quaternary (di)cationic triamantane derivatives G1 and G3 by the permethylation of the corresponding primary ammonium ions G2 and G4. The complexation behaviors of G1–G4 toward CB[7] and CB[8] were examined by 1 H NMR spectroscopy, which reveals that CB[8] is capable of fully encapsulating G1–G4 whereas CB[7] forms inclusion complexes with G1, G2, and G4 but cannot fully encapsulate the central hydrophobic core of the bis-quaternary ammonium ion G3. The geometries of the CB[ n ]-guest complexes were determined by analyzing the complexation induced changes in chemical shifts and were further confirmed by molecular modelling using the Conformer–Rotamer Ensemble Sampling Tool (CREST) based on the GFN methods. Finally, the complexation thermodynamics were determined by a combination of 1 H NMR competitive experiments, direct isothermal titration calorimetry (ITC) measurements, and competitive ITC titrations using a tight binding ternary complex as a competitor.  more » « less
Award ID(s):
1807486
NSF-PAR ID:
10435834
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
New Journal of Chemistry
Volume:
47
Issue:
11
ISSN:
1144-0546
Page Range / eLocation ID:
5338 to 5346
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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