Supramolecular Aggregation of Perfluoroorganyl Iodane Reagents in the Solid State and in Solution

Abstract

The crystal structures of different perfluoroorganyl iodanes are described, including those of four new benziodoxole derivatives with RF = n‐C3F7, n‐C4F9, n‐C8F17, and C6F5. In all of the compounds, the iodine atom shows significant Lewis acidity, and the fourth coordination site is readily filled by secondary bonding interactions to produce square‐planar coordination. Although this geometry is a good model for benziodoxoles, benziodoxolone derivatives tend to aggregate further through additional weak I···O or I···aryl contacts. The different interactions lead to the formation of various assemblies with different dimensions in the solid state. The protonation of the reagents results in the formation of entirely different supramolecular structures, which are supported by hydrogen bonding. The structural features of the reagents in the solid state reflect well their behavior in solution, and the I–C(RF) bond is influenced by the coordination of Lewis basic solvents to the iodine atom and by hydrogen bonding with protic solvents. These solvent effects are more pronounced for reagents containing the trifluoromethyl fragment than for derivatives with longer RF chains.