Cocrystal Assembled by 1,2‐Diiodotetrafluorobenzene and Acridine via CI···N Halogen Bond and π‐hole···F Bonds

Abstract

AbstractThe concepts on σ‐hole and π‐hole bonds are suggested. A cocrystal with repeated 8‐F‐atom unit as basic structural motif is assembled based on bifurcated CI···N···IC halogen/σ‐hole bond and antiparallel double π‐hole···F bonds by 1,2‐diiodotetrafluorobenzene and acridine and characterized well by XRD, powder XRD and solid 19F NMR, etc. Also the calculated interaction energies are −26.8 and −31.5 kJ/mol for bifurcated CI···N sp2 halogen bonds, and −14.3 kJ/mol for a pair of π‐hole···F bonds. In this system CI···N halogen bond has stronger competitive ability to CI···π halogen bond due to stronger basicity of N than π‐system in acridine. The combination of the halogen/σ‐hole and π‐hole bonds or together with other weak interactions could play a key role in assembling function materials, molecular recognition and design of drugs and so on.