Chalcogen Bonds in Crystals of Bis(o-anilinium)diselenide Salts

The diselenide moiety is labeled as a novel and robust chalcogen bond (ChB) donor group. The molecular electrostatic potential of two prototype diselenide derivatives shows the presence of two σ-holes along both the covalent bonds in which each selenium atom is involved. The propensity of selenium atoms of diselenides to work as electrophilic sites is confirmed by computational studies on the bis(o-anilinium)diselenide cation, and single crystal X-ray analysis of salts of this cation reveals the presence of close selenium⋯anion contacts. Comparison with halogen bonds in crystal structures of ionic δ 3 -iodane derivatives supports the rationalization of these close contacts as charge-assisted ChBs. Discrete adducts or two-dimensional networks are formed, suggesting the profitable use of the diselenide moiety in ChB based crystal engineering.