SYNTHESIS, SOLUTION AND MAGIC-ANGLE-SPINNING SN-119 NUCLEAR-MAGNETIC-RESONANCE STUDIES AND CRYSTAL-STRUCTURES OF DITHIOETHER COMPLEXES OF TIN(IV) HALIDES

The compounds SnX(4) reacted with 1 molar equivalent of dithioether, L -L, in dry CHCl3 solution to give the six-co-ordinate species [SnX(4)( L-L)] [X = Cl, L-L = MeS(CH2)(n)SMe, o-C6H4(SMe)(2) or PhS(CH2)(n)SPh (n = 2 or 3); X = Br, L-L = MeS(CH2)(n)SMe or o-C6H4(SMe)(2)] in high yield as white or pale yellow powdered solids. Using SnBr4 and PhS(CH2 )(n)SPH or SnI4 with MeS(CH2)(n)SME did not produce isolable products, although solution Sn-119-{H-1} NMR spectroscopy provided evidence for their existence at low temperatures. X-Ray structural studies on [SnC l4{MeS(CH2)(2)SMe}], [SnCl4{MeS(CH2)(3)SMe}], [SnCl4{o-C6H4(SMe)(2)}], [SnCl4{PhS(CH2)(3)SPh}] and [SnBr4{MeS(CH2)(3)SMe}] confirmed an S(2) X(4) donor set with the dithioether acting as a bidentate chelate. Var iable-temperature solution H-1 and Sn-119-{H-1} NMR spectroscopic stud ies showed that the complexes are extremely labile and ligand dissocia tion and pyramidal inversion are fast except at low temperatures. Magi c angle spinning Sn-119 NMR data for [SnCl4(L-L)] are reported. The cr ystal structure of cis-[SnI4{MeS(O)(CH2)(3)SMe}(2)], obtained as decom position product from the SnI4-MeS(CH2)(3)SMe reaction, shows monodent ate sulfoxide (O) co-ordination.