Crystal structures of 2,2'-bipyridyltetrafluorosilicon(IV), 2,2'-bipyridyltetrafluorogermanium(IV), and 2,2'-bipyridyltetrafluorotin(VI)

Abstract

The molecular structures of 2,2'-bipyridyltetrafluorosilicon(IV), SiFeCloHsNa, 2,2'-bipyridyltetrafluorogermanium(IV), GeFaClaH&p, and 2,2'-bipyridyltetrafluorotin(IV), SnF4CloHsNz, have been determined by single-crystal X-ray diffraction. The compounds were crystallized from nitromethane, and in the case of the germanium and tin complexes, two modifications of each were obtained:The unit cell constants are as follows: for SiF&HsNz, space group P21/c (no. 14), 2 = 4, a = 7.195 (2), b = 9.185 ( 2 ) , c = 16.821 (5) A, fi =, 106.85 (2)"; foi GeF4CIoHJTz.CH3N02, space group P21/m (no. l l ) , 2 = 2, a = 11.958 (3), b = 6.924 (2), c = 8.317 (2) A , p = , 96.16 (2)'; for S~F~C~O H & . C H~T~O~, space group P21/c (no. 14), 2 = 4, a = 8.844 (2), b = 11.646 (4), c = 13.420 (5) A , p = 94.04 (2)'. The stable forms of the germanium and tin complexes are possibly disordered, either in space group P62 (no. 171) or space group P64 (no. 172), where a = 11.631 (3), b = 20.319 ( 5 ) A and a = 12.06 (3), b = 20.56 (5) A, respectively; the crystal structures remain unsolved. All three compounds are monomeric, the solvent is not coordinated, and the coordination is the expected distorted cis octahedral.an unsolvated form and a monosolvated form, unstable t o loss of solvent on air-drying.

Crystal and molecular structure of 1,2,3,4,5,6,7,8-octaethylporphinatodichlorotin(IV) nitromethane solvate

“…Bond lengths and angles for either orientation are not particularly good. They agree only roughly with those found for the nitromethane molecule of solvation in the structure determination of 2,2'-bipyridyltetrafluorotin(IV) (Adley et al, 1972). Fig.…”

“…In the case of ClzSnOEP the only required crystallographic symmetry is a center of inversion, but the angle between adjacent rings is 0.4. ° Deviations from the least-squares plane passing through the metal and macrocyclic atoms are shown in Table 7; the greatest deviation is 0.02 A for N (2).…”

“…1. ORTEP drawing of 1, 2,3,4,5,6,7, showing numbering scheme and tin-ligand atom distances. Atoms not labelled are centrosymmetrically related.…”

(Dimethylaminomethyl)trifluorosilane, Me2NCH2SiF3—A Model for the α‐Effect in Aminomethylsilanes

“…[17] The coordination geometry at the silicon atoms is almost trigonal bipyramidal. The axial SiÀF bond lengths (trans to the Si···N bonds) are 1.641 (1) and are therefore longer than the equatorial SiÀF bonds (1.601(2) and 1.603(2) ).…”

Tin(IV) Fluoride Complexes with Tertiary Phosphane Ligands – A Comparison of Hard and Soft Donor Ligands

“…Some examples were reported in the period , often as part of larger surveys including the heavier tin(IV) halides, but little data were provided and only a single complex, [SnF 4 (2,2Ј-bipy)], was structurally characterised. [11][12][13][14][15][16] There appear to be no reports of SnF 4 complexes with softer donor ligands. This neglect in part is similar to that of other p-block fluorides, whose Lewis acidity, except towards F -or in superacid media (for MF 5 , M = As or Sb), is little explored, but also reflects the more difficult synthetic entry into the complexes.…”