Momeni Hasan, Rad-Moghadama Kurosh
Department of Organic Chemistry, University of Guilan, University Campus 2, Rasht, Iran.
Department of Organic Chemistry, Faculty of Chemistry, University of Guilan, Rasht, 41938-33697, Iran.
Sci Rep. 2025 May 26;15(1):18339. doi: 10.1038/s41598-025-03597-1.
New energetic heteroanionic dicationic ionic liquids (HeDILs) were synthesized from the reaction of epichlorohydrine and 1-methylimidazole in one-pot operation. Upon setting the reaction conditions, these simple and readily available starting materials delivered a fairly high yield of the ionic liquid consisting of 1,1'-(2-hydroxy-1,3-propandiyl)bis[3-methyl-1H-imidazolium] dication paired with two different anions. The as-prepared HeDIL allows the selective metathesis of its chloride anion, leading to production of analogous energetic HeDILs. The synthesized HeDILs were characterized experimentally by NMR and FT-IR spectroscopies, TGA and DSC thermal analysis and titrimetric anion measurements. The effect of anionic heterogeneity on configuration and energy of the HeDILs was explored by DFT computations. These calculations delineate a half-cup shape for the dominant conformation of the dication with its interior site being preferred by ClO occupation. This insight accounts for the relative resistance of ClO toward anion metathesis reaction of the parent HeDIL. Thermal analysis of the parent HeDIL by using a model-free iso-conversional method revealed that its exothermic decomposition has a complex kinetics.
新型高能杂阴离子双阳离子离子液体（HeDILs）通过一锅法操作由环氧氯丙烷与1-甲基咪唑反应合成。设定反应条件后，这些简单且易于获得的起始原料可得到相当高收率的由1,1'-（2-羟基-1,3-丙二基）双[3-甲基-1H-咪唑鎓]双阳离子与两种不同阴离子配对组成的离子液体。所制备的HeDIL可实现其氯离子的选择性复分解反应，从而生成类似的高能HeDILs。通过核磁共振（NMR）、傅里叶变换红外光谱（FT-IR）、热重分析（TGA）、差示扫描量热法（DSC）热分析以及滴定法阴离子测量等实验手段对合成的HeDILs进行了表征。通过密度泛函理论（DFT）计算探究了阴离子异质性对HeDILs构型和能量的影响。这些计算描绘出双阳离子主要构象呈半杯状，其内部位点更易被ClO占据。这一见解解释了ClO对母体HeDIL阴离子复分解反应的相对抗性。采用无模型等转化率方法对母体HeDIL进行热分析表明，其放热分解具有复杂的动力学。
