Porous Halogen‐Bonded Frameworks Assembled through Hetero‐polytopic Ion Pair Templation

Abstract Halogen‐bonding (XB) interactions have been extensively studied in the preparation of crystalline frameworks, yet porous 3D framework materials built on XBs remain elusive. The donor‐acceptor interactions are strengthened by use of anionic XB acceptors; however, the requisite charge‐balancing cations typically disrupt the framework and occupy potential void space. In this work, we prepare a tetratopic XB donor bearing a crown ether moiety for sodium cation sequestration. We show that when this ionpair receptor is crystallised with NaCl it gives a 3D framework that is porous to solvent and vapour, and undergoes single‐crystal‐to‐single‐crystal reactions.