(OC-6-33)-(2,2′-Bipyridine-κ2 N,N′)trimethyl(2-methylsulfanyl-2-thiazoline-κN)platinum(IV) tetrafluoridoborate

The asymmetric unit of the title complex, [Pt(CH3)3(C10H8N2)(C4H7NS2)]BF4, contains two crystallographically independent molecules. The PtIV atom in each complex cation exhibits a distorted octahedral coordination geometry, built up by three methyl ligands in a facial binding fashion, a bipyridine ligand and a monodentately N-bound 2-methylsulfanyl-2-thiazoline ligand (configuration index: OC-6–33). In the crystal structure, weak intermolecular C—H⋯F hydrogen bonds are found between the complex cations and BF4 − anions.

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HY2325).

Comment
Due to the low-spin d 6 electron configuration of platinum(IV), ligand substitution reactions of Pt(IV) complexes may be hampered. Starting from complexes exhibiting a PtMe 3 unit (Clegg et al., 1972;Lindner et al., 2008;Vetter et al., 2006Vetter et al., , 2010, substitution reactions were found to proceed smoothly even with weak donors (Steinborn & Junicke, 2000) because the leaving ligand is additionally activated by the high trans effect of a methyl ligand in trans position.
The asymmetric unit of the title compound consists of two symmetrically independent, structurally very similar molecules of two cationic Pt(IV) complexes [PtMe 3 (mttz-κN)(bpy)] + (mttz = 2-methylsulfanyl-2-thiazoline, bpy = 2,2'-bipyridine) as well as two BF 4 anions (Fig. 1). The primary coordination geometry of the Pt IV atom in the cationic complex is built up by three methyl ligands in a facial binding fashion, a bpy ligand and a monodentately bound mttz ligand (  Allen, 2002)]. The conformation of the five-membered thiazoline rings could be described as distorted half chair along C5-C6 and C22-C23, respectively (Bucourt, 1974). In the crystal of the title complex, weak intermolecular C-H···F hydrogen bonds were found between the cationic Pt(IV) complexes and BF 4 anions (Table 2).

Experimental
Under anaerobic conditions [PtMe 3 I(bpy)] (70 mg, 0.13 mmol) and AgBF 4 (26 mg, 0.13 mmol) were stirred in acetone (10 ml) for 30 min under absence of light. The precipitated AgI was filtered off and the colorless, clear filtrate was added to 2-methylsulfanyl-2-thiazoline (18 mg, 0.13 mmol) (Bose et al., 1973). The reaction mixture was stirred for 15 h, then the solvent was reduced in vacuo to 1 ml, layered with diethyl ether (3 ml) and cooled to -40°C. After 12 h the title complex was obtained as needles.

Refinement
All H atoms were positioned geometrically and allowed to ride on the respective parent atoms, with C-H = 0.95-0.99 Å and U iso (H) = 1.2U eq (C). The highest residual electron density was found 0.98 Å from Pt2 and the deepest hole 0.89 Å from Pt1.  Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.