Zhang Yaping, Zhen Bin, Li Hansheng, Feng Yaqing
School of Chemical Engineering and Technology, Tianjin University Tianjin 300072 China
School of Chemistry and Chemical Engineering, Beijing Institute of Technology Beijing 102488 China.
RSC Adv. 2018 Oct 31;8(64):36769-36774. doi: 10.1039/c8ra06378h. eCollection 2018 Oct 26.
Basic imidazolium-based ionic liquids not only possess the extraordinary physicochemical properties of ionic liquids, but also have excellent basicity and surfactivity. 1-Propyl-3-alkylimidazole hydroxide ionic liquids ([PRIm][OH]) were synthesized and their catalytic and surfactant behavior were studied in this work. [PRIm][OH] owned excellent surfactivity, and their alkyl chains and ion pairs benefit hydrophobicity and hydrophilicity respectively. The surfactivity of [PRIm][OH] increased with increasing alkyl chain length. [PRIm][OH] showed better catalytic performance than NaOH in the condensation of 2-aminobenzonitrile with cyclohexanone in aqueous medium, and the catalytic performance was well coincident with their surfactant behavior. [PRIm][OH] could decrease the interfacial tension of solvent effectively and form micelles in water. The formed micelles could solubilise more reactants into water and effectively increase the chance of contact between reactants and catalytic active sites. The catalyst dosage obviously affected catalytic performance. The catalytic system is a promising recyclable system.
基于咪唑的碱性离子液体不仅具有离子液体非凡的物理化学性质，还具有出色的碱性和表面活性。本文合成了1-丙基-3-烷基咪唑氢氧化离子液体（[PRIm][OH]），并研究了它们的催化和表面活性剂行为。[PRIm][OH]具有出色的表面活性，其烷基链和离子对分别有利于疏水性和亲水性。[PRIm][OH]的表面活性随烷基链长度的增加而增强。在水介质中，[PRIm][OH]在2-氨基苯甲腈与环己酮的缩合反应中表现出比NaOH更好的催化性能，其催化性能与其表面活性剂行为高度吻合。[PRIm][OH]能有效降低溶剂的界面张力并在水中形成胶束。形成的胶束可将更多反应物溶解于水中，并有效增加反应物与催化活性位点之间的接触机会。催化剂用量对催化性能有明显影响。该催化体系是一种很有前景的可循环利用体系。
