Dokument

Summary:
In the preceding work, some topics of organotin chalcogenide chemistry were added to this field regarding the following four aspects: i) the synthesis of new bis[tris(arylchalcogenolato)stannyl]organyls; ii) the potential physical and chemical applications of the newly synthesized bis[tris(arylchalcogenolate)stannyl]organyl compounds; iii) the reactivity of bis(trichlorostannyl)organyls or triorganotin chloride towards coinage metal complexes in the presence of PhSeSiMe3; and iv) the reactivity of bis(trichlorostannyl)organyls towards chalcogenide or/and transition metal complexes under solvothermal condition. This way, the work intended to a) explore whether arylchlcogenolato complexes of bis(trichlorostannyl)organyls are possible precursors for thermolysis for the synthesis of tin chalcogenide materials or serve as donor ligands for linkage of transition metal ions or for the formation of metal chalcogenolate complexes b) explore whether the reactivity of bis(trichlorostannyl)organyls toward chalcogenide or chalcogenolate and transition metals lead to the formation of organo-clad or organo-bridged complexes or clusters. Bis(trichlorostannyl)organyl compounds (Cl3Sn–R–SnCl3) were reacted with sodium thiophenolate in methanol or with 2-thionaphthol in toluene in the presence of triethylamine as a base to end up with the formation of bis[tris(arylthiolato)stannyl]organyls of the general type [(R,S)3Sn–R–Sn(SR,)3] (1-5). The selenium analogue of compounds 1-5 were synthesized by reaction of bis(trichlorostannyl)organyl compounds with diaryl diselenide in presence of a reducing agent (NaBH4) in ethanol. These reactions gave rise for the synthesis of compounds 6-11. In ensuing studies, the bis[tris(arylchalcogenolato)stannyl]organyl compounds prepared as discussed above were used as synthons for the synthesis of tin chalogenide materials or metal-arylchalcogenolato clusters. Thermolysis of (PhS)3Sn–Bu–Sn(SPh)3 and (PhSe)3Sn–Bu–Sn(SePh)3 lead to the formation of binary SnS2 and SnSe2 at 375 and 335 ºC. (PhSe)3Sn–Bu–Sn(SePh)3 was reacted with palladium acetate in dichloromethane to end up with a tetrameric complex of palladium and selenophenolate, [Pd(SePh)(OAc)]4 (12). Compound 12 possesses rectangular Pd4 arrangement.In order to explore the reactivity, bis(trichlorostannyl)organyl compounds were reacted with PhSeSiM3 and triphenyl phosphine complexes of coinage metals (Cu, Ag). The reaction of bis(trichlorostannyl)organyl with (PPh3)3AgNO3 a neutral tetradecanuclear silver cluster, [(Ph3PAg)8(SePh)12(μ6-Se)Ag6]•6THF (14) was obtained. In both cases, bis(trichlorostannyl)organyl compounds were not incorporated into the products. The reaction of triphenyltin chloride or tricyclohexyltin chloride instead of bis(trichlorostannyl)organyls with PhSeSiM3 and (PPh3)3AgNO3 resulted in an ionic silver selenide cluster, [(Ph3PAg)8(SePh)12(μ6-Se)0.5Ag6][Ph3SnCl2]•6THF (15) or [(Ph3PAg)8(SePh)12(μ6-Se)0.5Ag6][Cy3SnCl2] (16). Here, cationic Ag14Se12.5 cluster cores covered by an organic blanket. The pecularty of these latter compounds is the s.o.f. = 0.5 at the central µ6–Se ligand. Thus, half of the clusters in 15, 16 contain a central Se ligand, whereas the other half exhibits an empty cluster center. The structures of the statistically distributed neutral and +2 charged clusters in 15, 16 are averaged over the crystal. The potentially free site within the 14 silver atoms rationalize the highgrade of disorder of the cluster atoms and correlate with the facts that some coinage metal chalcogenide clusters are able to capture E2– ions. An according reaction of bis(trichlorostannyl)butane with elemental sulfur in ethylenediamine under solvothermal condition resulted in the formation of a polymeric compound [SnS2•en] (17). In order to compare the reactivity of the bis(trichlorostannyl)butane precursor with metallic tin, metallic tin and elemental sulfur were reacted under the indentical reaction condition as for the synthesis of compound 17. The latter ended up with the formation of a thiostannate salt, [enH]4[Sn2S6]•en (18). Methanothermal (solvothermal) reaction of bis(trichlorostannyl)butane with Na2S•9H2O and (PPh3)3CuCl finally led to the formation of an organyl-clad Sn/Cu/S cluster, [(Ph3PCu)6{cyclo-(CH2)4SnS2}6Cu4Sn] (19), combining three peculiarities at once: being (a) mixed-metallic, (b) mixed-valent, and (c) walnut-type with a metalloid core, a metal sulfide shell and an organic surface. DFT calculations rationalized the electronic situation and showed that the observed intramolecular cyclization of n-butyl groups at the Sn atoms is thermodynamically not favored. Hence, the formation should be driven mainly by the reductive sulfidic conditions that led to the observed formation of elemental sulfur and reduction of SnIVCl4 to SnIICl2.

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