Room-Temperature Synthesis of Thiostannates from {[Ni(tren)]2[Sn2S6]}n.

The compound {[Ni(tren)]2[Sn2S6]}n (1) (tren = tris(2-aminoethyl)amine, C6H18N4) was successfully applied as source for the room-temperature synthesis of the new thiostannates [Ni(tren)(ma)(H2O)]2[Sn2S6]·4H2O (2) (ma = methylamine, CH5N) and [Ni(tren)(1,2-dap)]2[Sn2S6]·2H2O (3) (1,2-dap = 1,2-diaminopropane, C3H10N2). The Ni-S bonds in the Ni2S2N8 bioctahedron in the structure of 1 are analyzed with density functional theory calculations demonstrating significantly differing Ni-S bond strengths. Because of this asymmetry they are easily broken in the presence of an excess of ma or 1,2-dap immediately followed by Ni-N bond formation to N donor atoms of the amine ligands thus generating [Ni(tren)(amine)](2+) complexes. The chemical reactions are fast, and compounds 2 and 3 are formed within 1 h. The synthesis concept presented here opens hitherto unknown possibilities for preparation of new thiostannates.

Crystal structure of tris-(N-methyl-salicylaldiminato-κ(2) N,O)vanadium(III).

The structure of the title complex, [V(C8H8NO)3], comprises neutral and discrete complexes, in which the V(III) cation is coordinated by three anionic N-methyl-alicylaldiminate ligands within a slightly distorted mer-N3O3 octa-hedral geometry. In the crystal structure, the mol-ecules are linked via C-H⋯O hydrogen bonds into supra-molecular chains that extend along the c axis.

Crystal structure of tris-(N-methyl-salicyl-aldiminato-κ(2) N,O)chromium(III).

The crystal structure of the title compound, [Cr(C8H8NO)3], is isotypic with the vanadium(III) analogue. The asymmetric unit consists of one Cr(3+) cation and three N-methyl-salicylaldiminate anions. The metal cation is octa-hedrally coordinated by three N,O-chelating N-methyl-salicylaldiminate ligands, leading to discrete and neutral complexes. In the crystal, neighbouring complexes are linked via C-H⋯O hydrogen-bonding inter-actions into chains propagating parallel to the c axis.

Influence of the synthesis parameters onto nucleation and crystallization of five new tin-sulfur containing compounds.

The distinct control of the synthesis parameters achieved crystallization of five new inorganic-organic hybrid tin sulfides with 1,10-phenanthroline (phen) as the organic component: {[Mn(phen)2]2(µ2-Sn2S6)} (1, 3), {[Mn(phen)2]2(µ2-Sn2S6)}·phen (2), {[Mn(phen)2]2(µ2-Sn2S6)}·phen·H2O (4), and {[Mn(phen)2]2[µ-η(2)-η(2)-SnS4]2[Mn(phen)]2}·H2O (5). Compounds 1, 3, and 4 occur successively under static conditions by increasing the reaction time up to 8 weeks. Stirring the reaction mixtures and keeping the educt ratio constant allow preparation of distinct phase pure samples within very short reaction times. At higher autogenous pressure, crystallization and conversion of several compounds are suppressed, and only 1 crystallized. Compound 2 could only be obtained in glass tubes at low pH value of the reaction mixture or at low amine concentration. Adjusting the pH value of the solution, the concentration, and the volume of the solvent, compounds 1-4 crystallize sequentially and were successively converted into each other. Results of thermal stability experiments and solubility studies suggest that compounds 1 and 3 are polymorphs following the density rule. Compounds 2 and 4 may be viewed as pseudopolymorphs of 1 and 3.