Metal-Involving Bifurcated Halogen Bonding with Iodide and Platinum(II) Center.

The cocrystallization of -[PtI(NCR)] (R = NMe, NEt, Ph , o-ClCH) with iodine and iodoform gave the crystalline adducts ∙4I, ∙2CHI, ∙2CHI, and ∙4I, whose structures were studied by single-crystal X-ray diffractometry (XRD). In the structures, apart from the rather predictable C-H⋯I hydrogen bonds (HBs) and I-I⋯I or C-I⋯I halogen bonds (XBs) with the iodide ligands, we identified bifurcated I-I⋯(I-Pt) and C-I⋯(I-Pt) metal-involving XBs, where the platinum center and iodide ligands function as simultaneous XB acceptors toward σ-holes of I atoms in I or CHI. Appropriate density functional theory (DFT) calculations (PBE-D3/jorge-DZP-DKH with plane waves in the GAPW method) performed with periodic boundary conditions confirmed the existence of the bifurcated metal-involving I-I⋯(I-Pt) and C-I⋯(I-Pt) interactions and their noncovalent nature.