Mutual Synergistic Regulation of Chloride Anion and Cesium Cation Binding Using A New Designed Macrocyclic Multi-functional Sites Receptor: A Case of DFT Computational Prediction

The mutual synergistic regulation of the multi-functional sites on single receptor molecule for ion-bingding/recognition is vital for new receptor design and need to be well explored from the experiment and theory. In this work, a new macrocyclic ion receptor (BEBUR) with three functional zones including two ether holes and one biurea groups is designed expecting to mutually enhance the ion-binding performance. The binding behaviors of BEBUR mainly for Cl^- and Cs⁺ are deeply investigated by using density functional theoretical calculations. It is found that Cl^-/Cs⁺ binding can be mutually enhanced and synergistically regulated via corresponding conformational changes of receptor, well reflecting an electrical complementary matching and mutual reinforcement effect. Moreover, solvent effect calculations indicate that BEBUR may be an excellent candidate structure for Cl^--bingding with the enhancement of counter ion (Cs⁺) in water and toluene. Additionally, visualization of intermolecular noncovalent interaction (NCI) is used for the analysis on the nature of the binding interactions between receptor and ions.