Isolation and Characterization of a Non‐Rigid Hexamethylbenzene–SO2+ Complex

Abstract During our studies towards the preparation of the pentagonal‐pyramidal hexamethylbenzene dication C6(CH3)62+, we isolated the unprecedented dicationic species C6(CH3)6SO2+ (AsF6−)2 from the reaction of hexamethylbenzene with a mixture of anhydrous HF, AsF5, and liquid SO2. This compound can be understood as a complex of unknown SO2+ with hexamethylbenzene. Herein, we report on its synthesis, molecular structure, and spectroscopic characterization.