From J. Am. Chem. Soc.:
Selective Fluorescent Detection of RNA in Living Cells by Using Imidazolium-Based Cyclophane
An imidazolium-based cyclophane was found to display turn on fluorescence in the presence of RNA molecules. Ionic interactions between the positively charged imidazolium groups and the anionic RNA backbond, along with pi-pi interactions, are invoked as reasons why this molecule selectively binds RNA. In any case, the synthesis could be of interest to those of you working with NHCs.