Crystal structure of bis(acetonitrile-κN)(4,4′-di-tert-butyl-2,2′-bipyridine-κ2 N,N′)platinum(II) bis(tetrafluoridoborate) packing as head-to-head dimers

The bulky tert-butyl groups of the dbbpy ligand do not preclude the formation of head-to-head dimers in the crystal structure of bis(acetonitrile)(4,4′-di-tert-butyl-2,2′-bipyridine)platinum(II) tetrafluoridoborate.


Chemical context
The title compound is soluble in a diverse range of solvents and possesses exchangeable acetonitrile ligands for facile incorporation of novel ligands to develop new and diverse behaviors of platinum(II) complexes. The solubility and apt geometry of the (dbbpy)platinum(II) complex make it a desirable building block for coordination-driven self-assembly of homo-metallic (Zhang, et al., 2017) and hetero-metallic (Bera et al., 2001) supramolecular complexes. This platinum(II) diimine can also be combined with dithiolene ligands to study methylation kinetics (Stace, et al., 2016), generate charge-transfer materials (Smucker, et al., 2003), or make model complexes for examining photophysical properties (Lazarides, et al., 2011;Yang et al., 2014).

Structural commentary
The platinum-nitrogen distances for the bipyridyl N1 and N2 of the +2 cation are 1.994 (4) and 1.995 (4) Å , respectively, with a bond angle of 80.5 (2) . These are shorter than those affected by the stronger trans-influence of chloride in two

Synthesis
The synthesis of the title compound used a method which replaced the chloride from Pt(dbbpy)Cl 2 (Tzeng et al., 2001) 696 Joseph et al. Displacement ellipsoid plot (50% probability of all non-H atoms), illustrating the slightly canted head-to-head dimer with selected intramolecular distances shown.
Yellow crystals of the title compound were grown from liquid diffusion of hexanes into a dilute acetone solution.

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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.