In the Pursuit of Efficient Anion-Binding Organic Ligands Based on Halogen Bonding

The syntheses and the crystal structures of new multitopic anion-binding organic ligands based on a benzenoid scaffold and bearing two or three 2-iodo-imidazolium arms are reported. The quite short C–I···Br¯ contacts observed in the solid state (0.77 times the normalized contacts) demonstrate the excellent halogen bonding donor ability of iodine atoms in 2-iodoimidazolium cations. The geometric features of obtained bromide anion adducts afford valuable structural insights for the design of effective and selective multitopic anion receptors based on halogen bonding.