Bis(trimethylammonium) tetrachloridodiphenylstannate(IV)

The title compound, [(CH3)3NH]2[Sn(C6H5)2Cl4], consists of [(CH3)3NH]+ cations and [SnPh2Cl4]2− anions in which the Sn atom, located on a centre of inversion, is bonded to four Cl atoms and two phenyl rings, giving an octahedral geometry with the phenyl rings in trans positions. In the crystal, the cations and the anions are connected by N—H⋯Cl hydrogen bonds and C—H⋯Cl interactions.

The title compound, [(CH 3 ) 3 NH] 2 [Sn(C 6 H 5 ) 2 Cl 4 ], consists of [(CH 3 ) 3 NH] + cations and [SnPh 2 Cl 4 ] 2À anions in which the Sn atom, located on a centre of inversion, is bonded to four Cl atoms and two phenyl rings, giving an octahedral geometry with the phenyl rings in trans positions. In the crystal, the cations and the anions are connected by N-HÁ Á ÁCl hydrogen bonds and C-HÁ Á ÁCl interactions.

Comment
Our interest for organotin(IV) compounds is related to the various applications found for this family of compounds (Evans & Karpel, 1985;Kapoor et al., 2005;Zhang et al., 2006). Many compounds containing the [SnPh 2 Cl 4 ] 2ion in the cis or trans conformation have been reported (Ouyang et al., 1998;Hazell et al., 1998;Fernandez et al., 2002;Venkatraman et al., 2004;Garcia-Seijo et al., 2001;Teoh et al., 1992). In our search for new organotin(IV) compounds we have initiated here the study of the interactions between (CH 3 ) 3 N.HCl and SnPh 2 Cl 2 , which has yielded the title compound.
In the [Ph 2 SnCl 4 ] 2anion, the tin atom is located on a centre of inversion and is bonded to four Cl atoms and two phenyl groups giving an octahedral geometry with the phenyl groups in trans-positions (Fig. 1). Consequently, the angle between the two trans groups is exactly 180 ° while the phenyl rings are almost perpendicular to the equitorial SnCl~4~ plane [C1-Sn1-Cl1 = 89.39 (6)°, C1-Sn1-Cl2 = 90.86 (7) In the crystal the anion and the cations are linked by N-H···Cl hydrogen bonds (Fig. 1) and C-H···Cl intermolecular interactions (Table 1).

Experimental
The title compound was obtained as a white crystalline solid by reacting trimethylammonium chloride with diphenyltin dichloride in chloroform (2/1 ratio; M.p: 443 K). After slow evaporation of the solvent colourless crystals, suitable for X-ray diffraction analysis, were obtained.

Refinement
The NH H-atom was located in a difference Fourier map and was freely refined. The C-bound H-atoms were included in calculated positions and treated as riding: C-H = 0.95 and 0.98 Å for CH and CH 3 H-atoms, respectively, with U iso (H) = k × U eq (C), where k = 1.2 for CH H-atoms, and k = 1.5 for CH 3 H-atoms.
supplementary materials sup-2 Figures   Fig. 1. The molecular structure of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level [the C-bound H-atoms have been omitted for clarity; symmetry code: (') = -x + 1, -y + 1, -z + 1].

Special details
Experimental. multi-scan from symmetry-related measurements Sortav (Blessing 1995) Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix.
The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles 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 > σ(F 2 ) is used only for calculating Rfactors(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.