Synthesis and characterization of novel Wells-Dawson-type mono vanadium(V)-substituted tungsto-polyoxometalate isomers: 1- and 4-[S2VW17O62](5-).

Two vanadium(V)-substituted tungsto-polyoxometalate isomers, 1- and 4-[S2VW17O62](5-), were prepared as their tetra-alkyl ammonium salts from a W(VI)-H2SO4-V(V) reaction mixture in aqueous CH3CN solution. X-ray crystallographic structural analysis revealed that both isomers have a Wells-Dawson-type structure with a higher occupancy of vanadium at polar sites and belt sites for 1- and 4-[S2VW17O62](5-), respectively. The isomers were also characterized by elemental analysis, infrared, Raman, UV-vis, and (51)V NMR spectroscopies as well as voltammetry, and the data obtained were compared with that derived from [S2W18O62](4-).

Penta-aqua-tri-μ(3)-hydroxido-tris-(imino-diacetato)-μ(3)-oxido-tetra-hedro-calcium(II)tricobalt(III) 2.54-hydrate.

In the title compound, [CaCo(3)(C(4)H(5)NO(4))(3)(OH)(3)O(H(2)O)(5)]·2.54H(2)O, the Co atom is octa-hedrally coordinated by one imino-diacetate (ida) dianion as a facial O,N,O'-tridentate ligand, two μ(3)-OH groups and one μ(3)-O ligand, forming an partial Co(3)O(4) cubane cluster. This unit coordinates to a Ca(II) cation in an O,O',O''-tridentate fashion, generating a distorted CaCo(3)O(4) cubane-type cluster.

Nitro-syltris(pyridine-2-thiol-ato-κN,S)molybdenum(II) dihydrate.

In the title compound, [Mo(C(5)H(4)NS)(3)(NO)]·2H(2)O, the Mo atom is coordinated by a nitrosyl ligand and three monoanionic N,S-bidentate ligands in a distorted MoN(4)S(3) penta-gonal-bipyramidal mol-ecular geometry. The pyridine N atom of one pyridine-2-thiol-ate (pyt) ligand is coordinated to the Mo atom in the trans position relative to the NO ligand [N(pyt)-Mo-N(NO) = 170.62 (19)°].

trans-(Pyrimidine-2-thiol-ato-κN,S)[tris-(2-amino-ethyl)amine-κN,N',N'',N''']cobalt(III) chloride hexa-fluoridophosphate.

In the title compound, [Co(C(4)H(3)N(2)S)(C(6)H(18)N(4))](Cl)PF(6), the Co(III) ion is coordinated by a tripod-like tetra-dentate ligand and a monoanionic N,S-bidentate ligand in an approximately octa-hedral CoN(4)OS geometry. The anionic S atom of the pyrimidine-2-thiol-ate (pymt) ligand is coordinated in the trans position to the primary amine N atom (Nprim) of the tris-(2-amino-ethyl)amine (tren) ligand. The crystal structure exhibits short inter-molecular N-H⋯N hydrogen bonds (N⋯N <3.