Pnicogen and chalcogen bonds in cyclometalated iridium(III) complexes

Reaction of organoiridium(III)-2-phenylpyridine complex, [Ir(ppy)2(μ-Cl)]2 (ppy = 2-phenylpyridinato-C2,N), with 4-(2-bromophenyl)-1,2,3-thiodiazole (X) or 4-(2-bromophenyl)-1,2,3-selenadiazole (Y) in CH2Cl2 yields to [Ir(ppy)2Cl(X)]·CH2Cl2 (1) or [Ir(ppy)2Cl(Y)] (2), respectively. Both compounds were characterized by characterized by elemental analyses (C, H, N), HRESI+-MS, FTIR, and studied by single-crystal X-ray diffraction. The coordination environment of the central iridium(III) has a distorted octahedral geometry, four sites being occupied by two (ppy)−, which chelates in the C,N fashion, while the two other sites are filled with the Cl− and X (or Y) ligands. The intramolecular S···N and Se···Cl types of chalcogen bonds were found in the structures of 1 and 2, respectively. Compound 1 is also present intramolecular pnicogen bonding and intermolecular halogen bonding (between CH2Cl2 molecules) with the short N···Br (3.160 A) and Cl···Cl (2.187 A) distances. The crystal structures in 1 and 2 are stabilized by medium-strong intermolecular hydrogen bonding interactions.