Madeira Pedro P, Passos Helena, Gomes Joana, Coutinho João A P, Freire Mara G
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
Phys Chem Chem Phys. 2017 May 10;19(18):11011-11016. doi: 10.1039/c6cp08210f.
Although highly relevant to a priori select adequate solvents for a given application, the determination of the hydrogen-bond acidity or proton donor ability of aqueous solutions of ionic liquids is a difficult task due to the poor solubility of the commonly used probes in aqueous media. In this work, we demonstrate the applicability of the pyridine-N-oxide probe to determine the hydrogen-bond acidity of both neat ionic liquids and their aqueous solutions, based on C NMR chemical shifts, and the suitability of these values to appraise the ability of ionic liquids to form aqueous two-phase systems.
尽管为特定应用预先选择合适的溶剂具有高度相关性，但由于常用探针在水性介质中的溶解度较差，因此测定离子液体水溶液的氢键酸度或质子供体能力是一项艰巨的任务。在这项工作中，我们基于碳核磁共振化学位移，证明了吡啶-N-氧化物探针可用于测定纯离子液体及其水溶液的氢键酸度，以及这些值在评估离子液体形成双水相系统能力方面的适用性。
