A Self-Assembled Cage Binds Xenon via Xe-F Dispersion Interactions

We report the synthesis of a series of structurally analogous tetrahedral imine cages with controlled variation in the number and position of fluorine atoms. Among these, only the cage (F2) with 12 inwardly directed fluorine atoms exhibits affinity for xenon in both chloroform and tetrachloroethane. Cages lacking fluorine (F0), having outwardly directed fluorine (F3), or featuring rotatable fluorine groups (F1) show negligible binding. These results, combined with cavity volume analysis and theoretical calculation, indicate that Xe-F London dispersion forces and size complementarity are the dominant factors for Xe recognition in solution.