Chiral Cyclic Hypervalent Iodine(III) for Halogen Bonding–Mediated Dimerization and Modulable Chirality Induction in Solution

A challenge exists in the solution-phase construction of chiral functional materials via halogen bonding, largely due to the pronounced disruptive influence of solvation on conventional halogen bonding interactions. In this work, we describe halogen bond–mediated chirality induction in solution, enabling the construction of discrete-state chiroptical materials with tunable properties and broad substrate versatility. A central chiral site was introduced into a cyclic hypervalent iodine(III) scaffold (denoted as I(III)), which individually assembles into cationic antielectrostatic halogen-bonded dimers in the solid state and low-polarity solvents, stabilized by a quadrupled halogen and hydrogen bonding network. I(III) exhibits strong binding affinity toward both neutral and anionic halogen bond acceptors, with association constants on the order of ∼10 4 M –1 . This robust interaction enables efficient chirality induction in both the ground and excited states. The resulting halogen-bonded complexes display solvent-responsive behavior, exhibiting mirror-image chiroptical properties in dichloromethane and tetrahydrofuran. It demonstrates excellent adaptability toward diverse halogen bond acceptors, enabling effective chirality induction across a range of systems. This versatility facilitates the realization of full-color circularly polarized luminescence.