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Aggregation‐induced emission (AIE) materials have drawn great attention for applications as organic light‐emitting diodes (OLED) and probes. The applications are, however, restricted by the complex syntheses and hydrophobic properties. Herein, a one‐step synthesis of an AIE material based on imidazole hydrazone is assessed. Protonation of the imidazole‐H leads to emission color change from yellow to green in the solid state. The emission color is recovered upon imidazole‐H+ deprotonation. Moreover, the emission wavelength shifts from 532 to 572 nm by anion exchange. In addition, an enhanced emission (ΦF up to 22.6 %) was obtained with the Br− anion compared with NTf2−, SbCl5−, PF6−, and OTf− anions. X‐ray crystallography studies together with theoretical calculations show that the enhanced emission of hydrazone salts arises from strong hydrogen bonding between the hydrazone proton and the halide ion (Cl− or Br−). [ABSTRACT FROM AUTHOR]

A novel strategy based on the concept of preorganization and cooperation has been designed for a superior capacity to capture low-concentration CO2 by imide-based ionic liquids. By using this strategy, for the first time, an extremely high gravimetric CO2 capacity of up to 22 wt % (1.65 mol mol−1) and excellent reversibility (16 cycles) have been achieved from 10 vol. % of CO2 in N2 when using an ionic liquid having a preorganized anion. Through a combination of quantum-chemical calculations and spectroscopic investigations, it is suggested that cooperative interactions between CO2 and multiple active sites in the preorganized anion are the driving force for the superior CO2 capacity and excellent reversibility. [ABSTRACT FROM AUTHOR]

The separation and recycling of catalyst and cocatalyst from the products and solvents are of critical importance. In this work, a class of functionalized ionic liquids (ILs) were designed and synthesized, and by tuning the hydrophilicity and hydrophobicity of cation and anion, respectively, these ILs could reversibly transfer between water and organics triggered upon undergoing a temperature change. From a combination of multiple spectroscopic techniques, it was shown that the driving force behind the transfer was originated from a change in conformation of the PEG chain of the IL upon temperature variation. By utilizing the novel property of this class of ILs, a highly efficient and controllable CuI-catalyzed cycloaddition reaction was achieved wherein the IL was used to entrain, activate, and recycle the catalyst, as well as to control the reaction. [ABSTRACT FROM AUTHOR]