Gelation, Self-Assembly, and Acid Responsive Properties of an Unsymmetrical 1,3,4-Oxadiazole Derivative

A novel unsymmetrical 1,3,4-oxadiazole derivative (2-POXD-B8) was synthesized. 2-POXD-B8 can form organogel in methanol. The gelation and self-assembly behavior of 2-POXD-B8 were researched by SEM, XRD, UV-vis, and temperature-dependent FT-IR, etc. pi-pi interaction and van der Waals force are viewed as the main driving forces in the self-assembly process. In addition, 2-POXD-B8 showed acid-responsive properties in different states, including gel state and film state. A dual-channel acid response by reversible solution-gel transition and fluorescence changes was observed in the methanol gel system. The protonation of 2-POXD-B8 is the reason for its acid-responsive property.