A Brönsted basicity scale (∼24 pK units) for 85 commonly seen imidazole-, imidazoline-, triazole-, and thiazole-based N-heterocyclic olefins (NHOs) in DMSO was established using a well-examined computational model. The influence of substituents on the Brönsted basicities of these NHOs was investigated through basicity comparisons and rationalized by geometric analyses. The Gibbs energy (ΔG_r) of the reaction between NHO and CO₂ was also calculated, which linearly correlates with the basicity of the corresponding NHO, suggesting that the stability of NHO–CO₂ adducts can be evaluated by the basicity of NHOs and a stronger basicity leads to a more stable NHO–CO₂ adduct.

中文翻译：

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DMSO中N-杂环烯烃的布朗斯台德碱度：评估NHO-CO2加合物稳定性的有效方法。

使用经过仔细检查的计算模型，建立了DMSO中85种常见的咪唑基，咪唑啉基，三唑基和噻唑基N杂环烯烃（NHO）的布朗斯台德碱度标度（约24 p K单位）。通过碱度比较研究了取代基对这些NHO的Brönsted碱度的影响，并通过几何分析对其进行了合理化。还计算了NHO和CO ₂之间反应的吉布斯能量（ΔG _r），它与相应NHO的碱性呈线性关系，这表明可以通过NHO和CO ₂的碱性来评估NHO-CO ₂加合物的稳定性。较强的碱度导致更稳定的NHO-CO ₂加合物。