Tetrakis(2,4,6-trimethylanilido)tin(IV)

The molecular structure of Sn(NHMes)4 is defined by a central tin(IV) atom that is coordinated by four NHMes groups in a distorted tetrahedral arrangement.

The packing diagram (Fig. 2) indicates that the molecules of (1) are arranged in undulating layers parallel to (001) in the solid state.The NH groups do not participate in hydrogen bridges.This is obviously due to the steric shielding of the bulky mesityl residues.

Synthesis and crystallization
All manipulations were carried out under an argon atmosphere.n-Hexane was freshly distilled from lithium aluminium hydride.Sn(NMe 2 ) 4 was prepared according to the literature (Jones & Lappert, 1965).
2.5 g (18.4 mmol) of mesityl amine were added to a solution of 1.36 g (4.61 mmol) of Sn(NMe 2 ) 4 in 30 ml of n-hexane.The reaction slowly turned pale yellow and a colourless precipitate was formed.After 12 h the reaction mixture was filtered and 300 mg of the product were received.The filtrate was stored at 253 K to give another 0.83 g of yellowish crystals of the title compound.Combined yield: 1.13 g (38%).

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.The amino hydrogen atom was located from a difference-Fourier map and was refined freely.

Table 2
Experimental details.