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Anion influences on reactivity and NMR spectroscopic features of NHC precursors.

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 ¹³C_C2 NMR resonances, while ¹ J _C2-H coupling constants appear to be anion and solvent independent.

SUBMITTER: Huynh HV

PROVIDER: S-EPMC9087444 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Anion influences on reactivity and NMR spectroscopic features of NHC precursors.

Huynh Han Vinh HV Lam Truc Tien TT Luong Huyen T T HTT

RSC advances 20181012 61

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 e ...[more]

PMID: 35547036

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