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Updated: Sep 23, 2025

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Anion influences on reactivity and NMR spectroscopic features of NHC precursors
Han Vinh Huynh1, Truc Tien Lam1, Huyen T T Luong1
1Department of Chemistry, National University of Singapore 3 Science Drive 3 117543 Singapore Republic of Singapore chmhhv@nus.edu.sg +65 6779 1691 +65 6516 2670.
Abstract:
A series of 16 benzimidazolium salts of the type iPr2-bimyH+X- with various anions X were synthesized and characterized by various spectroscopic and spectrometric methods. Significant anion and solvent effects on the chemical shifts of the C2-H protons were found, which allows for a ranking of the anions in terms of their hydrogen-bond acceptor properties. Stronger acceptors could increase the acidity of their respective salts leading to a faster H/D exchange. Similar but less pronounced anion influences were detected for the 13CC2 NMR resonances, while 1 J C2-H coupling constants appear to be anion and solvent independent.
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