Zur Existenz schwacher Wechselwirkungen zwischen Sb(III) und Phenylgruppen: Sb2Br6(SPPh3)2, Sb2I6(SePPh3)2 · 2 CH2Cl2, Sb4Br12(SPMe2Ph)4 und (Ph4P)2Sb2Br8 · CH3CN / On the Existence of Weak Interactions between Sb(III) and Phenyl Groups: Sb,Br6(SPPh3)2, Sb2I6(SePPh3)2 · 2CH2Cl2, Sb4Br12(SPMe2Ph)4 and (Ph4P)2Sb2Br8 · CH3CN

Abstract

The compounds Sb2Br6(SPPh3)2 (1), Sb2I6(SePPh3)2·2CH2Cl2 (2), and Sb4Br12(SPMe2Ph)4 (3) were prepared in nearly quantitative yield by reacting of SbBr3 or SbI3 with the corresponding thio- or selenophosphoranes in dichloromethane solution. The reaction of SbBr3 and Ph4PBr in acetonitrile solution yields (Ph4P)2Sb2Br8 · CH3CN (4). The crystal structures of compounds 1-4 were determined from single crystal X-ray diffraction data. 1: monoclinic, space group P21/n with a = 875.3(1), b = 1366.0(1), c = 1837.0(1) pm, β = 100.28(1)°, V = 2161.1 × 106 pm3 and Z =2. 2: monoclinic, P21/n, a = 1021.6(4), b = 1285.7(4), c = 2088.8(6) pm, β = 96.45(3)°, V = 2726.4 × 106 pm3, Z = 2. 3: monoclinic, P21/n, a = 1180.5(1), b = 1407.9(1), c = 1891.5(2) pm, β = 106.35(2)°, V = 3016.6 × 106 pm3, Z = 2. 4: monoclinic, C 2/c, a = 2213.1(2), b = 1387.5(1), c = 1955.6(1) pm, β = 112.33(1)°, V = 5523.2 × 106 pm3, Z = 4. 1,2 and the anion of 4 contain centrosymmetric dimeric units with bridging halogen atoms. In all three compounds weak interactions between antimony and phenyl groups complete the sixfold coordination of Sb(III) (Sb-C: 339-365 pm). The crystal structure of 3, however, exhibits tetramers [SbBr3(SPMe2,Ph)]4 with bridging halogen and sulfur atoms, and without Sb-phenyl contacts. The conclusion from the different structures is that there is only a minor structural influence of the observed weak interactions