8种双阳离子吡啶基离子型化合物的合成、表征与热稳定性能

Synthesis and Characterization of Eight Pyridine-based Dicationic Ionic Compounds and Their Thermal Stability

吡啶分别与4种二卤代烃进行N-烷基化反应得到4种双阳离子吡啶基离子型卤化物,再与硝酸银进行阴离子交换得到4种相应的硝酸盐。分别对它们的结构进行了1HNMR1、3CNMR表征,并测定了它们的溶解性及热稳定性。结果表明,这8种双阳离子型化合物的溶解性相似,易溶于极性溶剂,难溶于非极性溶剂。在8种双阳离子吡啶基离子型化合物中,氯化物的热稳定性要高于相应的硝酸盐。随着连接双阳离子的烃基增大,相同阴离子的双阳离子化合物的热稳定性增加。而且双阳离子吡啶基离子型化合物的热稳定性高于含相同阴离子的单阳离子吡啶基离子液。

Four chlorides of pyridine-based dicationic ionic compounds were synthesized by Nalkylation of pyridine with dihalogenated hydrocarbons, and then by exchange of the anion with silver nitrate, the corresponding four nitrates of the ionic compounds were obtained. Structures of eight dicationic ionic compounds were characterized by ^1HNMR and ^13 CNMR. The solubility behavior of eight dicationic ionic compounds are similar. They are soluble in polar solvent and insoluble in nonpolar solvent. The thermal stability of the chlorides are higher than the corresponding nitrates, and, with increasing length of hydrocarbon linkage, the thermal stabilities of dicationic ionic compounds with the same anion increased. Besides, the thermal stability of dicationic ionic compound is higher than monocationic ionic liquid with the same anion.