ILPC: simple chemometric tool supporting the design of ionic liquids

Abstract

BackgroundIonic liquids (ILs) found a variety of applications in today’s chemistry. Since their properties depend on the ions constituting particular ionic liquid, it is possible to synthetize IL with desired specification, dependently on its further function. However, this task is not trivial, since knowledge regarding the influence of particular ion on the property of concern is crucial. Therefore, there is a strong need for new, fast and inexpensive methods supporting the process of ionic liquids’ design, making it possible to predefine IL’s properties even before the synthesis.ResultsWe have developed a simple tool (called Ionic Liquid PhysicoChemical predictor: ILPC) that allows for the simultaneous qualitative prediction of four physicochemical properties of ionic liquids: viscosity, n-octanol–water partition coefficient, solubility and enthalpy of fusion. By the means of Principal Component Analysis, we studied 172 ILs and defined distribution trends of those four properties, dependently on the ILs structures. We proved that the qualitative prediction of mentioned properties could be performed on the basis of most simple information we can deliver about ILs, which are their molecular formulas.ConclusionsCreated tool presented in this paper allows fast, pre-synthesis screening of ILs, with the omission of any experimental steps. It can be helpful in the process of designing ILs with preferred properties. We proved that the information encrypted in molecular formula of ionic liquid could be a valuable source of knowledge regarding the IL’s viscosity, n-octanol–water partition coefficient, solubility and enthalpy of fusion. Moreover, we proved that the influence of both ions, constituting the IL, on each of those four properties indicates same, additive trend.Graphical AbstractSchematic representation of ILPC performance - the exact position of the ionic liquid on the linear map is determined by its chemical structureElectronic supplementary materialThe online version of this article (doi:10.1186/s13321-016-0152-4) contains supplementary material, which is available to authorized users.

Modeling from Theory and Modeling from Data: Complementary or Alternative Approaches? The Case of Ionic Liquids

“…A simple chemometric tool, the IL physicochemical (ILPC) predictor, which provides a preliminary qualitative prediction of properties, such as viscosity, has recently been reported . The authors state that viscosity depends mainly on hydrogen‐bond formation, but “unfortunately this type of intermolecular relation is not covered by our set of descriptors”.…”

“…In particular, PP− 2 is related to the hydrophilic/hydrophobic character, whereas PP− 3 is related to anionic size/shape and to the ability to form hydrogen bonds as a donor or acceptor. The latter intermolecular interaction, not covered by previous descriptors and described by PP− 3 , accounts for the good predictability of the present model. PP+ 1 embodies information related to cation solubility, size, flexibility, and molecular weight.…”

Chemometrics for Selection, Prediction, and Classification of Sustainable Solutions for Green Chemistry—A Review

“…Barycki et al proposed the application of PCA for the definition of the distribution trends of four IL properties dependently on their structures. Then CA is used to provide some detailed information concerning IL distribution [72]. It is also worth noting that chemometrics may be the basis for developing other tools.…”

Thermodynamic Properties and Intermolecular Interactions of a Series of N-Butylammonium Carboxylate Ionic Liquids

“…3−7 The investigations on physicochemical properties of ILs are also very necessary not only for designing chemical industry separation processes and transport equipment but also for predicting the properties and characteristics of ILs for the application in various fields. 8 Protic ionic liquids (PILs), generally more hydrophilic than aprotic ionic liquids (AILs), are a type of ILs with active protons. 9 Simple ammonium ILs from amines and acids by the neutralizing reaction belong to protic ionic liquids and are expected to be widely used in the extraction of metal ions, electrolyte of fuel cells, 10 and absorption of CO 2 , 11 etc.…”

“…Ionic liquids (ILs) have been favored by researchers from many fields over the past decade, due to their unusual properties and potential environmentally friendly behaviors. , In recent years, ILs have shown great promise in many respects such as catalytic reactions, organic synthesis, CO 2 capture, electrochemistry, extraction, and multiphase separations. − The investigations on physicochemical properties of ILs are also very necessary not only for designing chemical industry separation processes and transport equipment but also for predicting the properties and characteristics of ILs for the application in various fields …”