Redox reactive (RNC)CuII species stabilized in the solid state via halogen bond with I2

The crystal structure of [Cu2(μ-O)(μ-I)2(CNXyl)4]·I2 (2·I2) was determined from single-crystal X-ray diffraction data. The adduct 2·I2 represents the first example of structurally characterized isocyanide-copper(II) complexes. In the structure of 2·I2, 2 forms independent chains connected through molecular iodine via I···I–I···I halogen bonding. The DFT calculations and topological analysis of the electron density distribution within the formalism of Bader’s theory (QTAIM method) were performed for model complex 2·I2 and the obtained results allowed the attribution of these contacts to moderate strength (3.8–5.3 kcal/mol) non-covalent contacts exhibiting some covalent character.