Watanabe Satoshi, Ono Keigo, Nakayama Rinsuke, Tajiri Kaho, Inouchi Shun, Matsuo Takumi, Kunitake Masashi, Hayashi Shotaro
Division of Applied Chemistry and Biochemistry, Naitonal Institute of Technology, Tomakomai College, Nishikioka 443, Tomakomai, Hokkaido, 059-1275, Japan.
Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto City, Kumamoto, 860-8555, Japan.
Chemphyschem. 2024 Jun 3;25(11):e202300867. doi: 10.1002/cphc.202300867. Epub 2024 Apr 30.
Crystal engineering for single crystallization of π-conjugated molecules has attracted much attention because of their electronic, photonic, and mechanical properties. However, reproducibility is a problem in conventional printing techniques because control of solvent evaporation is difficult. We investigated the phase diagrams of two anthracene derivatives in synthesized ionic liquids for non-volatile crystal engineering to determine the critical points for nucleation and crystal growth. Anthracene and 9,10-dibromoanthracene were used as representative π-conjugated molecules that form crystal structures with different packing types. Ionic liquids with an alkylpyridinium cation and bis(fluorosulfonyl)amide were good solvents for the anthracene derivatives from ca. 0 °C to 200 °C. The solubilities (critical points for crystal growth) of the anthracene derivatives in the ionic liquids reached the 100 mM level, which is similar to those in organic solvents. Ionic liquids with phenyl and octyl groups tended to show high-temperature dependence (a high dissolution entropy) with 9,10-dibromoanthracene. The precipitation temperature (critical point for crystal nucleation) at each 9,10-dibromoanthracene concentration was lower than the dissolution temperature. The differences between the dissolution and precipitation temperatures (supersaturated region) in the ionic liquids were greater than those in an organic solvent.
由于其电子、光子和机械性能，用于π共轭分子单晶化的晶体工程备受关注。然而，在传统印刷技术中，再现性是一个问题，因为难以控制溶剂蒸发。我们研究了两种蒽衍生物在合成离子液体中的相图，以进行非挥发性晶体工程，从而确定成核和晶体生长的临界点。蒽和9,10 - 二溴蒽被用作代表性的π共轭分子，它们形成具有不同堆积类型的晶体结构。具有烷基吡啶鎓阳离子和双(氟磺酰基)酰胺的离子液体在约0 °C至200 °C的温度范围内是蒽衍生物的良好溶剂。蒽衍生物在离子液体中的溶解度（晶体生长的临界点）达到100 mM水平，这与在有机溶剂中的溶解度相似。含有苯基和辛基的离子液体与9,10 - 二溴蒽倾向于表现出高温依赖性（高溶解熵）。在每个9,10 - 二溴蒽浓度下的沉淀温度（晶体成核的临界点）低于溶解温度。离子液体中溶解温度和沉淀温度之间的差异（过饱和区域）大于有机溶剂中的差异。
