Another Example for the Ability of the Anion to act as a Bidentate Ligand: Solvothermal Synthesis, Crystal Structure, Calculated and Experimental Raman Spectra of [Cr(tren)SbS3]·H2O

The rare example of hybrid chalcogenoarsenates(III) incorporating trivalent vanadium complexes

A series of new hybrid vanadium chalcogenoarsenates(III) [VIII(en)2AsIIIS3] (1, en = ethylenediamine), [VIII(dap)2AsIIISe3] (2, dap = 1,2-diaminopropane), [VIII(teta)AsIIIQ3] {Q = S (3), Se (4), teta = triethylene-tetramine}, and [VIII2(en)6(μ2-O)][As2Se5] (5)...

The cation and anion bonding modes make a difference: an unprecedented layered structure and a tri(hetero)nuclear moiety in thioantimonates(V)

Mixing solutions of M²⁺ (M = Cu²⁺ or Zn²⁺) salts containing cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) as the ligand and an aqueous solution of Na₃SbS₄·9H₂O at room temperature led to the crystallization of two new compounds within minutes: {[Cu(cyclam)]₃[SbS₄]₂}_n·20nH₂O (I) and {[Zn(cyclam)]₃[SbS₄]₂}·8H₂O (II). In the structure of I [SbS₄]^3- anions acting as a tridentate ligand join CuN₄S₂ octahedra generating twelve-membered rings by corner-sharing of SbS₄ and CuN₄S₂ units. The rings are condensed into layers, which are stacked onto each other in a 6R polytype manner. The layers contain large pores with the water molecules located between the layers above and below the pores. In contrast, the structure of II comprises a discrete molecular tri(hetero)nuclear moiety with a bidentate [SbS₄]^3- anion connecting two rectangular pyramidal ZnN₄S polyhedra. The crystal water molecules of I and II can be thermally removed, and I and II are recovered by treatment under a humid atmosphere. The EPR spectrum of I indicates the presence of Cu²⁺ cations, which is unusual in the environment of S^2- anions. The different bonding situations and the preferences for the coordination geometries of Cu²⁺ and Zn²⁺ cations are rationalized by DFT based calculations, demonstrating that Cu²⁺ prefers an octahedral environment while Zn²⁺ adopts the square-pyramidal coordination. The pronounced differences in the vibrational spectra are also analyzed with DFT, showing how the different modes are influenced by the differing bond strengths.

A series of new vanadium(iii) chalcogenido-antimonates: an unusual seven-coordinate nitro-selenidovanadium(iii) complex

A series of new vanadium(iii) chalcogenidoantimonates [VIII(dap)2SbQ3] (Q = S (1), Se (2); dap = 1,2-diaminopropane), [H2dien][VIII2(en)2(dien)2(μ2-O)][SbSe4]2 (3, en = ethylenediamine; dien = diethylenetriamine) and [VIII(dien)2SbSe4] (4) have been solvothermally synthesized and structurally characterized. Both 1 and 2 contain neutral vanadium(iii)-centered complexes [VIII(dap)2SbQ3], where the [SbQ3]3- anion acts as a chelating ligand to complex [VIII(dap)2]3+, but they exhibit different molecular conformations. 3 consists of selenidoantimonate anions [SbSe4]3-, the protonated H2dien2+ cation, and the dinuclear complex [VIII2(en)2(dien)2(μ2-O)]4+ based on two [VIII(en)(dien)]3+ units bridged by one μ2-O group. 4 contains neutral [VIII(dien)2SbSe4] moieties with seven coordinated vanadium centres, which offers a rare example of high coordination of a nitro-selenidovanadium(iii) complex, mainly because the vanadium(iii) ion has a regular octahedral configuration based on the structures in the solid state. The optical, magnetic and photoelectronic properties of all compounds have been investigated, and the density functional theory calculation of 4 has also been studied.

Two manganese–amine complexes incorporating thioantimonates and exhibiting diversiform roles of amine ligands

Two manganese–amine complexes incorporating thioantimonates with diversiform structure-directing actions of the amine ligands have been synthesized and characterized.

A Mixed Valent Thioantimonate(III,V): [SbS3]3– and [SbS4]3– as bidentate ligands: Solvothermal synthesis and crystal structure of {Mn(dien)2}2[MnSb2S7]

The new compound {Mn(dien)2}2[MnSb2S7] (dien = diethylenetriamine) was obtained under solvothermal conditions and crystallizes in the orthorhombic space group Pbca. The main structural motif is the [MnSb2S7]4– anion being constructed by a [MnS4]6– tetrahedron, a [SbIIIS3]3– and a [SbVS4]3– anion. Each thioantimonate anion shares one edge with the Mn2+ centered cation generating the [MnSb2S7]4– unit. The two independent Mn2+ cations in the two {Mn(dien)2}2+ complexes are in a distorted octahedral environment of two tridentate acting dien molecules. One cation displays the λδ–λλ-conformation and the other the δλ–λδ-conformation. Several intermolecular S···H—N bonding interactions are found between the cations and the anions.

Octahedral monodithiolene complexes of cobalt(III) and chromium(III). Spectroscopic and density functional theoretical characterization of S,S'-coordinated benzene-1,2-dithiolate(1-) pi radicals

The reaction of [M(tren)Cl(2)]Cl (M = Co(III), Cr(III)) with benzene-1,2-dithiol, H(2)(bdt), and 3,6-bis(trimethylsilyl)benzene-1,2-dithiol, H(2)(tmsdt), in a water/methanol mixture in the presence of potassium tert-butoxide produced green crystals of [M(tren)(bdt)](PF(6))(1/2)(Cl)(1/2).H(2)O (1(PF(6))(1/2)(Cl)(1/2).H(2)O, M = Co; 2(PF(6))(1/2)(Cl)(1/2).H(2)O, M = Cr) and [M(tren)(tmsdt)](PF(6))(1/2)(Cl)(1/2).H(2)O (1a(PF(6))(1/2)(Cl)(1/2).H(2)O, M = Co; 2a(PF(6))(1/2)(Cl)(1/2).H(2)O, M = Cr), respectively, upon addition of KPF(6). The structures of 1(PF(6))(1/2)(Cl)(1/2).H(2)O and 2(PF(6))(1/2)(Cl)(1/2).H(2)O have been determined by X-ray crystallography. Octahedral 1 and 1a are diamagnetic whereas 2 and 2a possess an S = (3)/(2) ground state. Cyclic voltammetry of 1a and 2a in CH(2)Cl(2) solution established that both species undergo a reversible one-electron oxidation generating the stable dications [Co(III)(tren)(tmsdt(*))](2+) (S = (1)/(2)) and [Cr(III)(tren)(tmsdt(*))](2+) (S = 1) where (tmsdt(*))(1-) represents the pi radical monoanion of oxidized (tmsdt)(2-). The electrochemical oxidations are ligand centered processes. These dications have been investigated by UV-vis and EPR spectroscopy and density functional calculations using the B3LYP functional. The S,S'-coordinated benzene-1,2-dithiolate(1-) radical has been identified and unambiguously characterized. Comparison with the corresponding o-benzosemiquinonate(1-) complexes shows that the S,S'-coordinated benzene-1,2-dithiolate(1-) radical is a sulfur centered radical whereas its oxygen containing analogue carries approximately 65% of the spin density on the six-membered ring.