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

The crystal structure of [Cu-2(mu-O)(mu-I)(2)-(CNXyl)(4)] center dot I-2 (2 center dot I-2) was determined from single-crystal X-ray diffraction data. The adduct 2 center dot I-2 represents the first example of structurally characterized isocyanide-copper(II) complexes. In the structure of 2 center dot I-2, 2 forms independent chains connected through molecular iodine via I center dot center dot center dot I-I center dot center dot center dot 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 center dot I-2 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.