Crystal structure of the coordination compound of triiodidomethyltin(IV) with 2,2 '-bipyridine, MeSnI3 center dot bipy

The title compound, (2,2'-bipyridine-kappa N-2,N')triiodidomethyltin(IV), [Sn(CH3)-I-3(C10H8N2)], crystallizing in the non-centrosymmetric orthorhombic space group Pca2(1) as an inversion twin, represents one of the few structurally characterized coordination compounds of an organotin(IV) trihalide with 2,2'-biypridine. Its distorted octahedral geometry shows a meridional arrangement of the I atoms and the methyl group is in-plane with the five-membered chelate ring. Asymmetric bonding of the biypridine ligand to the tin(IV) atom is reflected by different Sn-N bond lengths [ 2.268 (4) angstrom versus 2.293 (4) angstrom] and caused by the static trans effect of the methyl group. Sn-I bond lengths show some differences with respect to their orientation to the methyl group or the bipyridine ligand, respectively. Angular distortions in the coordination sphere of the Sn-IV atom mainly arise from the large I atoms. Distortion of the 2,2'-bipyridine ligand as a result of its coordination to the Sn-IV atom are described by the twisting angle of 2.5 (2)degrees between the least-squares planes of the two pyridine rings, as well as by the angle of 6.2 (2)degrees between the two lines through the pyridine-connecting C atoms and the para-orientated C atoms. Directional intermolecular interactions are restricted to weak I center dot center dot center dot H van der Waals contacts.