Syntheses of [Pt6(CO)8(SnCl2)(SnCl3)4]4–and [Pt6(CO)8(SnCl2)(SnCl3)2(PPh3)2]2–Platinum–Carbonyl Clusters Decorated by SnIIFragments

The reaction of [Pt6(CO)6(SnCl2)2(SnCl3)4]4–(1) with CO under atmospheric pressure resulted in the new [Pt6(CO)8(SnCl2)(SnCl3)4]4–(2) cluster by the addition of two CO ligands and the elimination of a stannylene SnCl2group. In turn, 2 reacted with 2 equivalents of PPh3under a CO atmosphere to afford [Pt6(CO)8(SnCl2)(SnCl3)2(PPh3)2]2–(3) by elimination of two stannyl [SnCl3]–ligands. Conversely, the reaction of 2 with 2 equivalents of PPh3under a N2atmosphere resulted in a species tentatively formulated as [Pt6(CO)5(SnCl2)2(SnCl3)2(PPh3)2]2–(4–5CO) on the basis of13C NMR,31P NMR spectroscopy and ESI-MS studies. Compounds 2–4 were spectroscopically characterized by IR spectroscopy and multinuclear (13C and31P) variable-temperature NMR spectroscopy. The crystal structures of 2 and 3 were determined by means of single-crystal X-ray diffraction, and their bonding was computationally investigated by DFT calculations. The possible structure of 4–5CO was predicted by means of DFT methods.