Studies in aryltin chemistry III*. Crystal and molecular structures of tetra(p-methoxyphenyl)tin(IV) and tetra(p-methylthiophenyl)tin(IV)

Article abstract of DOI:10.1016/0022-328X(87)85126-4

Tetrakis(p-methylthiophenyl)tin(IV) (A) and tetrakis(p-methoxyphenyl)tin(IV) (B) have been prepared and their vibrational spectra (400-100 cm^-1) and X-ray crystal structures are reported.Both compounds are tetragonal with space group I4, Z = 2.For (A), a = b = 13.553(4), c = 7.442(2) Angstroem, and for (B), a = b =14.180(4), c = 6.303(2) Angstroem both at 173 K.Both structures were solved by the direct method and refined by full-matrix least squares calculations to R = 0.040, 767 observed reflections for A, and to R = 0.019, 721 observed reflections for B.Both molecules have 4 molecular symmetry with the CH3S or CH3O groups in the all-exo conformation almost coplanar with the phenyl rings.Increasing size of the para-substituent as CH3 is replaced by CH3O and then CH3S causes a decrease in d(Sn-C) from 2.147(6) to 2.136(4) and 2.123(7) Angstroem ascribed to increased intermolecular repulsions in the isomorphous close-packed structures.