Mixed Halide Tin(IV) Complexes with NN‐dimethylformamide and dimethylsulfoxide

By oxidative‐addition reactions of Br 2 and I 2 to SnCl 2 in the presence of NN‐dimethylformamide (DMF) and dimethylsulphoxide (DMSO), the mixed halide complexes SnCl 2 Br 2 L 2 (L DMF, DMSO) and SnCl 2 I 2 (DMSO) 2 are obtained. The IR, Raman and 119 Sn Mössbauer spectra suggest that the ligands coordinate in cis position through the oxygen atom, a C 1 symmetry being found for SnCl 2 I 2 (DMSO) 2 . SnCl 2 Br 2 (DMSO) 2 crystallizes in the triclinic space group P 1 with two molecules per unit cell. The lattice constants are a = 752.4, b = 1350.6, c = 820.3 pm, α = 89.60, β = 117.31 and γ = 90.83°. 2317 independent observed reflexions were used for refinement: R = 8.4%. The structure is disordered and our results are again consistent with a C 1 molecular symmetry. Mixtures of products were obtained by reaction of SnCl 2 with I 2 in the presence of DMF and by reaction of SnBr 2 with I 2 in the presence of DMSO.