| Summary: | 碩士 === 國立中正大學 === 化學所 === 95 === This project aims at the development of chemically stable ionic liquids. The cations of imidazolium and phosphonium were selected as our starting point to achieve the task.
We previously reported the room-temperature ionic liquid, [b-3C-im] [NTf2] was much more stable than the commonly used [bmim][PF6], [bdmim][PF6], and [bdmim][NTf2]. Based on the findings of this intriguing property, it prompted us to develop new synthetic scheme of this bicyclic ionic liquid, with the hope to achieve high overall isolated yields and to expand molecular diversity. Our new synthetic route was designed to prepare the fused imidazoles cations by using 4-chloro- butyronitrile or 5-chlorovaleronitrile as starting materials. Accordingly, a series of bicyclic imidazolium-based ionic liquids, [R-3C-im] and [R-4C-im], with the overall isolated yields of 40~53% were prepared facilely in only five steps. The yields were much improved as compared with the previously reported [b-3C-im][NTf2] (29%). Moreover, our new synthesis can conveniently prepare the related analogs.
For phosphonium ionic liquid research, the deuterium isotope exchange was employed to test chemical stability of the commonly used trihexyl(tetradecyl)phosphonium chloride. Our result revealed that the stability was not as good as reported in literature. As a result, we set out to develop and accordingly synthesize a new tricyclohexyl(tetradecyl)- phosphonium bromide ionic liquid. This compound is not only a chemically stable room-temperature ionic liquid, but also could be easily synthesized with high isolated yield (85%).
|
|---|
