Abstract
An acyl-amino acid type protic ionic liquid (PIL) composed of N-2-ethylhexylethylenediaminium ([HEtHex-en]+) coupled with dl-hexanoylalaninate ([Hexala]−), forming dl-[HEtHex][Hexala], was newly synthesized. This PIL has chelate moieties on both the cationic and anionic sides. It is a room-temperature ionic liquid with a glass transition temperature of 237.55 K (− 35.6 °C) and is highly miscible with water (H2O, 90 wt.%) owing to its high polarity. The dynamic viscosity approximately follows the Arrhenius equation while the electrical conductivity slightly deviates from it in the temperature range 303.15–353.15 K. The Walden line of dl-[HEtHex][Hexala] in the same temperature range is found to be outside the ΔW = 1 region. dl-[HEtHex][Hexala] enables the encapsulation of transition metal ions, and the measurements with inductive coupled plasma emission have shown that the solubilities of CuCl2, CoCl2 and NiCl2 in dl-[HEtHex][Hexala] are 74.5, 65.2, and 17.6 mmol·kg−1, respectively.
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Hua, E., Yasuda, H., Harada, M., Taguchi, E., Iida, M.: Formation of silver nanoparticles from ionic liquids comprising N-alkylethylenediamine: effects of dissolution modes of the silver(I) ions in the ionic liquids. Colloids Surf. A Physicochem. Eng. Asp. 522, 503–513 (2017)
Dupont, J., De. Souza, R.F., Zuarez, P.A.Z.: Ionic liquid (molten salt) phase organometallic catalysis. Chem. Rev. 102, 3667–3692 (2002)
Saravanamurugan, S., Kunov-Kruse, A.J., Fehrmann, R., Riisager, A.: Amine-functionalized amino acid-based ionic liquids as efficient and high-capacity absorbents for CO2. Chem. Sus. Chem. 7, 897–902 (2014)
Niedermaier, I., Bahlmann, M., Papp, C., Kolbeck, C., Wei, W.: Carbon dioxide capture by an amine functionalized ionic liquid: fundamental differences of surface and bulk behavior. J. Am. Chem. Soc. 136, 436–441 (2014)
Yasuda, T., Watanabe, M.: Protic ionic liquids: fuel cell applications. MRS Bull. 38, 560–566 (2013)
Nakamoto, H., Watanabe, M.: Brønsted acid–base ionic liquids for fuel cell electrolytes. Chem. Commun. 24, 2539–2541 (2007)
Ohira, K., Yoshida, K., Hayase, S., Itoh, T.: Amino acid ionic liquid as an efficient cosolvent of dimethyl sulfoxide to realize cellulose dissolution at room temperature. Chem. Lett. 41, 987–989 (2012)
Bell, J.R., Luo, H., Dai, S.: Superbase-derived protic ionic liquid extractants for metal ion separation. Sep. Purif. Technol. 130, 147–150 (2014)
Yao, M., Fan, M., Liang, Y., Zhou, F., Xia, Y.: Imidazoliun hexaflurophosphate ionic liquids as high temperature lubiricants for steel-steel contacts. Wear 268, 67–77 (2010)
Maton, C., Vos, N.D., Stevens, C.V.: Ionic liquid thermal stabilities: decomposition mechanisms and analysis tools. Chem. Soc. Rev. 42, 5963–5977 (2013)
Gathergood, N., Garcia, M.T., Scammells, P.J.: Biodegradable ionic liquids: Part I. Concept, preliminary targets and evaluation. Green Chem. 6, 166–175 (2004)
Jordan, A., Gathergood, N.: Biodegradation of ionic liquids—a critical review. Chem. Soc. Rev. 44, 8200–8237 (2015)
Wang, X.J., Chi, Y.L., Mu, T.C.: A review on the transport properties of ionic liquids. J. Mol. Liq. 193, 262–266 (2014)
Liaw, H.J., Chen, C.C., Chen, Y.C., Chen, J.R., Huang, S.K., Liu, S.N.: Relationship between flash point of ionic liquids and their thermal decomposition. Green Chem. 14, 2001–2008 (2012)
Pejakovi, V., Tomastik, C., Dörr, N., Kalin, M.: Influence of concentration and anion alkyl chain length on tribological properties of imidazolium sulfate ionic liquids as additives to glycerol in steel–steel contact lubrication. Tribol. Int. 97, 234–243 (2016)
Ohno, H., Fukumoto, K.: Amino acid ionic liquids. Acc. Chem. Res. 40, 1122–1129 (2007)
Fukumoto, K., Yoshizawa, M., Ohno, H.: Room temperature ionic liquids from 20 natural amino acids. J. Am. Chem. Soc. 127, 2398–2399 (2005)
Takemura, S., Kawakami, S., Harada, M., Iida, M.: Solvation structure of a copper(II) ion in protic ionic liquids comprising N-hexylethylenediamine. Inorg. Chem. 53, 9667–9678 (2014)
Nakayama, C., Harada, M., Iida, M.: Properties of protic ionic liquids comprised of N-alkyldiethylenetriamine and their complexation of copper(II) ions. Eur. J. Inorg. Chem. 31, 3744–3754 (2017)
Zhang, J.M., Zhang, S.J., Dong, K., Zhang, Y.Q., Shen, Y.Q., Lu, X.M.: Supported absorption of CO2 by tetrabutylphosphonium amino acid ionic liquids. Chem. Eur. J. 12, 4021–4026 (2006)
Zhan, Y.Q., Zhang, S.J., Lu, X.M., Zhou, Q., Fan, W., Zhang, X.P.: Dual amino-functionalised phosphonium ionic liquids for CO2 capture. Chem. Eur. J. 15, 3003–3011 (2009)
Hua, E., Xu, Y., Zhao, H.: Properties of mono-protic ionic liquids composed of hexylammonium and hexylethylenediaminium cations with trifluoroacetate and bis(trifluoromethylsulfonyl) imide anions. J. Mol. Liq. 276, 379–384 (2019)
Hua, E., Izutani, J., Gerille, N., Iida, M.: Aggregation of bis(N-octanoylaminocarboxylato) magnesium(II) complexes in water/organic solvents. Colloids Surf. A Physicochem. Eng. Asp. 392(1), 213–219 (2011)
Naren, G., Masuda, R., Iida, M., Harada, M., Kurosu, H., Suzuki, T., Kimura, T.: Formation of molecular glasses and the aggregation in solutions for lanthanum(III), calcium(II), and yttrium(III) complexes of octanoyl-dl-alaninate. Dalton Trans. 13, 1698–1709 (2008)
Naren, G., Yasuda, A., Iida, M., Harada, M., Suzuki, T., Kato, M.: Aggregation in methanol and formation of molecular glasses for europium(III) N-acylaminocarboxylates: effects of alkyl chain length and head group. Dalton Trans. 28, 5512–5522 (2009)
Wu, T.Y., Su, S.G., Gung, S.T., Lin, M.W., Lin, Y.C., Ou-Yang, I., Sun, W., Lai, C.A.: Synthesis and characterization of protic ionic liquids containing cyclic amine cations and tetrafluoroborate anion. J. Iran. Chem. Soc. 8, 149–165 (2011)
Hua, E., Wang, H.: Properties of protic ionic liquids composed of N-alkyl (= hexyl, octyl and 2-ethylhexyl) ethylenediaminum cations with trifluoromethanesulfonate and trifluoroacetate anion. J. Mol. Liq. 220, 649–656 (2016)
Glasser, L.: Lattice and phase transition thermodynamics of ionic liquids. Thermochim. Acta 421, 87–93 (2004)
Ghanem, O.B., Papaiconomou, N., Abdul Mutalib, M.I., Viboud, S., El-Harbawi, M., Uemura, Y., Gonfa, G., Azmi Bustam, M., Lévêque, J.-M.: Thermophysical properties and acute toxicity towards green algae and Vibrio fischeri of amino acid-based ionic liquids. J. Mol. Liq. 212, 352–359 (2015)
Dong, Y., Shah, S.N., Pranesh, M., Prokkola, H., Kärkkäinen, J., Leveque, J.-M., Lassi, U.K.C.: Lethesh: Azepanium based acyl-amino acid protic ionic liquids: synthesis, thermophysical properties and COSMO-RS study. J. Mol. Liq. 264, 24–31 (2018)
Kagimoto, J., Taguchi, S., Fukumoto, K., Ohno, H.: Hydrophobic and low-density amino acid ionic liquids. J. Mol. Liq. 153(2), 133–138 (2010)
Arkhipova, E.A., Ivanov, A.S., Maslakov, K.I., Savilov, S.V., Lunin, V.V.: Effect of cation structure of tetraalkylammonium-and imidazolium-based ionic liquids on their conductivity. Electrochim. Acta 297, 842–849 (2019)
Xu, W., Angell, C.A.: Solvent-free electrolytes with aqueous solution-like conductivities. Science 302, 422–425 (2003)
Li, C.G., Hua, E.: Effect of water content on the physicochemical properties of PIL composed of 2-ethylhexylethylenediaminium cation and CF3SO3 anion. J. Henan Normal Univ. (Nat. Sci. Ed.) 47(2), 61–66 (2019)
Walden, P.: Uber organische losungs-und ionisierungsmittel. III. teil: innere reibung und deren zusammenhang mit dem leitvermogen. J. Phys. Chem. 55, 207–249 (1906)
Schreiner, C., Zugmann, S., Hartl, R., Gores, H.J.: Fractional Walden rule for ionic liquids: examples from recent measurements and a critique of the so-called ideal KCl line for the Walden Plot. J. Chem. Eng. Data 55, 1784–1788 (2010)
Yoshizawa, M., Xu, W., Angell, C.A.: Ionic liquids by proton transfer: vapor pressure, conductivity, and the relevance of ΔpKa from aqueous solutions. J. Am. Chem. Soc. 125, 15411–15419 (2003)
Hua, E., Iida, M.: Protonation Properties, Applications and Effects: Properties of Protic Ionic Liquids Comprising N-Alkyl Polyamines (Chapter 3). Nova Science Publishers, Hauppauge (2019)
Acknowledgements
This work was financially supported by the Key Scientific Research Projects in 2019 at North Minzu University (Project No. 2019 KJ13) and National Natural Science Foundation of China (21663018). We are also grateful to Prof. Masayasu Iida of Nara Women's University for the helpful discussion. We would like to thank Editage (www.editage.com) for English language editing.
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Hua, E., Liu, J. & Naren, G. Studies on Amino Acid Type Protic Ionic Liquid Comprising N-2-Ethylhexylethylenediaminium Cation Coupled with the dl-Hexanoylalaninate Anion. J Solution Chem 50, 941–953 (2021). https://doi.org/10.1007/s10953-021-01097-0
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DOI: https://doi.org/10.1007/s10953-021-01097-0