Dynamic Combinatorial Chemistry of Ditellurides

Dynamic combinatorial chemistry enables the exploration of reversible chemical exchange reactions. Here, we report studies on the dynamic Te─Te bond exchange of chemically and structurally diverse ditellurides using ¹²⁵Te NMR spectroscopy. The results revealed rapid and unbiased equilibration, forming a consistent 1:1 distribution of reactants and products across all chemical systems. Extending to multi-component mixtures, we observed robust equilibrium formation even in complex systems involving multiple ditelluride species that can be easily distinguished by ¹²⁵Te NMR spectroscopy. In line with the NMR analyses showing that the Te─Te bond exchange efficiently proceeds in various solvents, at very low temperatures, in the absence of visible light, and in the presence of radical scavengers, quantum chemical analyses revealed that the ditelluride-ditelluride exchange likely proceeds via a non-synchronous concerted mechanism and not via an alternative radical mechanism. Integrated NMR spectroscopic and quantum chemical analyses also showed that the efficiency of the chalcogen-chalcogen exchange involving ditellurides follows the trend Te-Te > Te-Se > Te-S. Overall, the results indicate that ditellurides are excellent dynamic systems that may find applications across molecular sciences.