Treatment of dichlorobis(piperidine-1-carbonitrile)platinum(II) with potassium iodide in water/methanol mixture results in the halide ligand exchange giving novel trans-diiodobis(piperidine-1-carbonitrile)platinum(II) complex. The reaction proceeds under mild conditions (20°C, 40？min) giving trans-[PtI2(NCNC5H10)2] in 70% isolated yield. The iodide complex was characterized by IR, 1H and 13C NMR spectroscopies, and high resolution ESI-MS, and its structure was determined by a single crystal X-ray diffraction. 1. Introduction Interest in metal complexes bearing NCR (R = Alk, Ar, NAlk2) ligands is stimulated by enhanced reactivity of nitrile functionality in such compounds toward nucleophilic addition and 1,3-dipolar cycloaddition [1, 2]. Moreover, these metal-mediated processes allow the conductance of the reactions, which are not feasible without involvement of metal centers. Our recent results demonstrate unexpectedly high activity of platinum(II)-bound push-pull nitriles NCNAlk2 toward cycloaddition of nitrones and nucleophilic additions [3]. Following this project focused on investigations of unusual reactivity of push-pull nitrile ligands, we studied novel platinum(II) complex bearing push-pull dialkylcyanamide ligands. 2. Materials and Methods All reagents and solvents were obtained from commercial sources and used as received. Isomeric mixture of approximately 1？:？1 cis/trans-dichlorobis(piperidine-1-carbonitrile)platinum(II) was prepared in accordance with the published method [4]. Infrared spectrum was recorded on a Shimadzu FTIR 8400S instrument in KBr pellets. 1H and 13C NMR spectra were measured on a Bruker-DPX 300 and Bruker 400 MHz Avance spectrometers at ambient temperature. Electrospray ionization mass spectrum was obtained on a Bruker micrOTOF spectrometer equipped with electrospray ionization (ESI) source and MeOH was used as the solvent. The instrument was operated at positive ion mode using a m/z range of 50–3000. 2.1. X-Ray Crystal Structure Determination The crystal of of trans-[PtI2(NCNC5H10)2] was immersed in cryo oil, mounted in a Nylon loop, and measured at a temperature of 100？K. The X-ray diffraction data was collected on Bruker Kappa Apex II Duo diffractometer using Mo Kα radiation (λ = 0.71073？？). The SAINT program package [5] was used for cell refinement and data reduction. The structure was solved by direct methods using SHELXS-97 [6] program with a WinGX [7] graphical user interface. A numerical absorption correction (SADABS) [8] was applied to data. Structural refinement was carried out using SHELXL-97 [6]. Hydrogen
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