Crystal and molecular structure of triphenyl[2-(p-tolylthio)ethyl]tin

Abstract

The crystal and molecular structure of Ph₃SnCH₂CH₂SC₆H₄Me-p has been determined by X-ray crystallography. In each of the two independent molecules in the asymmetric unit the tin atom has an irregular tetrahedral geometry, with C−Sn−C valency angles ranging from 104.1(5) to 114.7(5)° in molecule (1) and from 104.6 to 112.7(6)° in molecule (2). The bond lengths, C_alkyl−Sn are 2.18(1) and 2.17(2)Å (in molecules (1) and (2), respectively) while the C_aryl−Sn bond lengths range from 2.11(1) to 2.13(1)Å in molecule (1) and from 2.09(1) to 2.14(1)Å in molecule (2). The Sn−C−C−S torsion angle, 172(1)° is the same for both molecules. NMR spectral data are presented; the¹H NMR spectrum in solution of the central-CH₂−CH₂-unit suggests that each of the protons on each of the CH₂ groups is magnetically distinct and that rotations about the C−C bond are slow on the NMR time scale. Comparisons with similar molecules are made and conformations discussed in terms of steric effects.