Dynamic Covalent Self‐Assembly of Chloride‐ and Ion‐Pair‐Templated Cryptates

While supramolecular hosts capable of binding and transporting anions and ion pairs are now widely available, self‐assembled architectures are still rare, even though they offer an inherent mechanism for the release of the guest ion(s). In this work, we report the dynamic covalent self‐assembly of tripodal, urea‐based anion cryptates that are held together by two orthoester bridgeheads. These hosts exhibit affinity for anions such as Cl(−), Br(−) or I(−) in the moderate range that is typically advantageous for applications in membrane transport. In unprecedented experiments, we were able to dissociate the Cs⋅Cl ion pair by simultaneously assembling suitably sized orthoester hosts around the Cs(+) and the Cl(−) ion.