cis-Dichloridobis[tris(4-chlorophenyl)phosphane-κP]platinum(II) acetonitrile monosolvate

The title compound, [PtCl2(C18H12Cl3P)2]·C2H3N, packs as monomeric units with a square-planar geometry around the PtII atom. The two tris(4-chlorophenyl)phosphane ligands are coordinated in a cis orientation, with P—Pt—P and Cl—Pt—Cl angles of 99.36 (2) and 88.02 (2)°, respectively. In the crystal, C—H⋯N interactions are observed between the phenyl rings and the acetonitrile solvent molecules.

The title compound, [PtCl 2 (C 18 H 12 Cl 3 P) 2 ]ÁC 2 H 3 N, packs as monomeric units with a square-planar geometry around the Pt II atom. The two tris(4-chlorophenyl)phosphane ligands are coordinated in a cis orientation, with P-Pt-P and Cl-Pt-Cl angles of 99.36 (2) and 88.02 (2) , respectively. In the crystal, C-HÁ Á ÁN interactions are observed between the phenyl rings and the acetonitrile solvent molecules.
The title compound compares well with other closely related Pt(II) complexes from the literature containing two chloro and two tertiary phosphane ligands in a cis geometry (Davis & Meijboom, 2011;Ogutu & Meijboom, 2011). The Pt-Cl and Pt-P bond lengths compare well with the typical values for complexes of this kind.
In the crystal structure, intermolecular C-H···N interactions are observed between phenyl rings and the acetonitrile solvent molecules.

Experimental
Tris(4-chlorophenyl)phosphane (0.1235 g, 0.34 mmol) was dissolved in ethanol (25 cm 3 ). Pt(COD)Cl 2 (0.05 g, 0.17 mmol) was added to the solution and the mixture was allowed to reflux for 24 h. The solvent was evaporated and a white solid was obtained. Colourless crystals were obtained by recrystallization from acetonitrile, crystals suitable for a singlecrystal X-ray diffraction study.

Refinement
All H positions were calculated after each cycle of refinement using a riding model, with C-H = 0.93 Å and U iso (H) = 1.2U eq (C) for aromatic H atoms, and with C-H = 0.96 Å and U iso (H) = 1.5U eq (C) for methyl H atoms. prepare material for publication: WinGX (Farrugia, 1999).

Figure 1
Representation of the title compound, showing the numbering scheme and displacement ellipsoids (50% probability). For the carbon rings, the first digit refers to ring number, second digit to atom in the ring. Hydrogen atoms omitted for clarity (except when involved in intermolecular interactions).

Crystal data
[PtCl 2 (C 18 H 12 Cl 3 P) 2 ]·C 2 H 3 N M r = 1038.24 Monoclinic, P2 1 /c Hall symbol: -P 2ybc a = 13.3604 (16) Special details Experimental. The intensity data was collected on a Bruker X8 Apex II 4 K Kappa CCD diffractometer using an exposure time of 20 s/frame. A collection frame width of 0.5 ° covering up to θ = 28.4° resulted in 99% completeness accomplished. Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.