Halogen and chalcogen bonding in dichloromethane solvate of cyclometalated iridium(III) isocyanide complex

Solvent-rich dichloromethane solvate of cis-[Ir(bptz)₂(CNXyl)₂]BF₄ (3, bptz is cyclometallated 4-(4-bromophenyl)-2-methylthiazole) is prepared via the reaction of chloro-bridged dimer [Ir(bptz)₂(μ-Cl)]₂ (1) with 2,6-dimethylphenyl isocyanide (CNXyl, 2) and AgBF₄. Single crystal X-ray diffraction on the 3·3¼CH₂Cl₂ solvate showed the presence of numerous non-covalent interactions, including the C–S···F–B chalogen bonding (ChB), the C–Br···Br–C, C–Cl···Br–C, and C–Cl···S(C)–C halogen bonding (XB), and the C–H···F–B hydrogen bonding (HB). The nature of these short contacts was explored both experimentally by single-crystal X-ray diffraction and theoretically by DFT calculations on the empirical geometries followed by Bader’s topological electron density distribution analysis. The evaluated energies of XBs and ChBs are in range 1.3–2.2 kcal/mol indicating the non-covalent nature of the contacts.