Solvent-dependent photophysical and anion responsive properties of one glutamide gelator

Abstract

One gelator consisting of four amide units and one chromophore was designed and synthesized. These four amide groups could induce the self-assembly of the gelator molecules in one-dimensional (1-D) direction. Two cyano and one nitro terminal groups were also appended into the chromophore as electron withdrawing groups to make the gelator’s own typical D–π–A electron structure. As a result, it was found that the color of the gel phases, the sol–gel phase transition temperature, microscopic morphologies, emission behaviour and response to anions were dependent on the solvent because of the different packing models and solvation effect in different solvents. For example, the color of the DMSO gel was orange, but ODCB gel possessed a yellow color. In addition, multicolor emission could be realized in DMSO gel systems, but ODCB gels only emitted yellow fluorescence. Moreover, the gelator was responsive to F⁻, H₂PO₄⁻ and OAc⁻ in DMSO, but in ODCB it selectively responded to F⁻.