Preparation of a Tetra-Imidazolium Salt and Sensing for p‑Dinitrobenzene

A macrocyclic tetra-imidazolium salt (2) based on quinoxaline was prepared and characterized. The recognition of 2 to nitro compounds was investigated by fluorescence spectroscopy, ¹H NMR titrations, MS, IR spectroscopy, and UV/vis spectroscopy. The results displayed that 2 was able to effectively differentiate p-dinitrobenzene from other nitro compounds via the fluorescence method.