Crystal structure of mer-tris{2,6-difluoro-3-[5-(2-fluorophenyl)pyridin-2-yl-κN]pyridin-4-yl-κC 4}iridium(III) dichloromethane hemisolvate n-hexane hemisolvate

Iridium(III) complexes based on 2,3′-bipyridine ligands are known to exhibit strong emission from blue to green that makes them of interest for organic light-emitting diodes and organic lighting uses. In the title compound, the IrIII ion adopts a distorted octahedral coordination environment defined by three C,N-chelating 2,6-difluoro-3-[5-(2-fluorophenyl)pyridin-2-yl]pyridin-4-yl ligands in a meridional manner. In the crystal, intermolecular C—H⋯F and C—H⋯π hydrogen bonds, as well as intermolecular C—F⋯π interactions, are present, leading to a two-dimensional network.


Chemical context
Phosphorescent iridium(III) complexes are considered to be excellent candidates for triplet emitters in phosphorescent organic light-emitting diodes (PHOLEDs) because of their high efficiency and high stability (Cho et al., 2016). In particular, iridium(III) complexes with C,N-chelating 2,3 0 -bipyridine ligands have recently attracted much attention because of their deep-blue emission and easy tuning emission energy upon ligand substitution . However, many studies of the crystal structures of bipyridine-based iridium(III) derivatives are focused on the different substituents of the C-coordinating pyridine ring (Lee et al., 2014). Examples of iridium(III) complexes with substituents on the Ncoordinating pyridine ring are relatively rare compared to those of C-coordination pyridine-functionalized iridium(III) complexes Oh et al., 2013). Herein, we report the result of our investigation of the crystal structure of an iridium(III) complex with an o-tolyl group on the Ncoordinating pyridine ring.

Structural commentary
The molecular structure of the title compound is shown in Fig. 1. The asymmetric unit consists of one Ir III atom, three 2,6-difluoro-3-[5-(2-fluorophenyl)pyridin-2-yl]pyridin-4-yl ligands, and half each of the n-hexane and dichloromethane View of the molecular structure of the title compound, showing the atomnumbering scheme. Displacement ellipsoids are drawn at the 50% probability level; dashed lines represent intramolecular C-HÁ Á ÁF and C-HÁ Á ÁN hydrogen bonds. The n-hexane and dichloromethane solvent molecules are not shown for clarity. Table 1 Selected geometric parameters (Å , ).  Hydrogen-bond geometry (Å , ).
No interactions between the n-hexane solvent molecules and the other components of the title compound are observed.

Synthesis and crystallization
The title complex was synthesized according to a previous report (Lee et al., 2017). Slow evaporation from a dichloro-methane/hexane solution afforded yellow crystals suitable for X-ray crystallography analysis. 1
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )