Nucleophilic attack at the carbon atom of a dithiocarbene ligand by coordinated carbon disulphide: The molecular structure of [(dppe)IPt(μ-C(S)SC(SMe)2)Pt(dppe)]+I− (dppe=1,2-bis(diphenylphosphino)ethane)

Reaction of the complex [Pt(η2-CS2)(dppe)] [dppe=1,2-bis(diphenylphosphino)ethane] with excess methyl iodide results in the formation in high yield of the dimeric complex [(dppe)IPt(μ-C(S)SC(SMe)2)Pt(dppe)]+I−·C7H8·Et2O, the crystal structure of which has been determined. Crystals of the complex are monoclinic, space group P21/c, with Z=4, in a unit cell with lattice parameters a=21.082(4), b=17.304(3), c=21.423(3) Å, and β=116.62(1)°. The structure has been refined to R1=0.054 (R2=0.059) for 4512 unique data and 333 variables. The complex consists of two distorted square-planar Pt fragments which are held together by a novel bridging CS2C(SMe)2 group. The complex has been independently prepared by the reaction of [Pt(η2-CS2)(dppe)] with the carbene complex [Pt(I)(dppe){C(SMe)2}]+I−, and has been further characterized by elemental analysis, 1H, 31P{1H} NMR, IR spectroscopy, and conductivity measurements.