Zur Koordinationschemie des 1,3-Dithiol-2-thion-4,5-diselenolats (dsit) – ein Vergleich mit 1,3-Dithiol-2-thion-4,5-dithiolat (dmit)

Coordination Chemistry of 1,3-Dithiole-2-thione-4,5-diselenolate (dsit) — Comparison with 1,3-Dithiole-2-thione-4,5-dithiolate (dmit) Synthesis and properties of metal(II) and/or metal(III) bis-chelates of 1,3-dithiole-2-thione-4,5-diselenolate (dsit) of general type (Bu₄N)_n[M(dsit)₂] (n = 2: M ? Zn, Cd, Hg, Cu, Ni, Pd, Pt; n = 1: M ? Ni, Au) are described. By comparison of the ir, ¹³C nmr, epr spectra, cyclovoltammetric data, and x-ray investigations (nickel-bis-chelates) of chelates of dsit and those of the chelates of 1,3-dithiole-2-thione-4,5-dithiolate (dmit) the consequences of selenium for sulfur substitution on position 4 and 5 of the heterocyclic ligand are discussed.     

S-(N-(Thiocarbamoyl)benzimido)-dithiocarbamidsäureester

Zusammenfassung Die Synthese der Titelverbindungen3 (R ¹=R ²=C₂H₅;n-C₄H₉) durch Reaktionen von N-(N,N-Diethylthiocarbamoyl)-benzimidoylchlorid (2) mit Natriumdialkyldithiocarbamaten (1) in Aceton wird beschrieben. Die niedrigen Ausbeuten (bis 25% d.Th.) sind durch Nebenreaktionen bedingt. Die Strukturen der Verbindungen werden durch IR-,¹H-NMR-,¹³C-NMR-und Massenspektren bestätigt. Nebenreaktionen werden¹³C-NMR-spektroskopisch verfolgt und die Ergebnisse diskutiert.

---

S-(N-(thiocarbamoyl)benzimido)dithiocarbamic esters

Summary The synthesis of the title compounds3 (R ¹=R ²=C₂H₅;n-C₄H₉) by reactions of N-(N,N-diethylthiocarbamoyl)benzimidechloride (2) with sodiumdialkyldithiocarbamates (1) in acetone is described. The low yields (<25%) are caused by the occurrence of side reactions. The structures of the compounds were confirmed by IR,¹H and¹³C NMR, and mass spectroscopy. Side reactions were detected by¹³C NMR spectroscopy; the results are discussed.

     

Die elektrochemische Reduktion von CSSe und CSe2 in Dimethylformamid: Heterocyclische 1,2-Dichalkogenolate und ihre Koordinationschemie

Electrochemical Reduction of CSSe and CSe₂ in Dimethylformamide: Heterocyclic 1,2-Dichalcogenolates and their Coordination Chemistry Starting from carbon diselenide or carbon selenidesulfide the electrochemical preparation (electrosynthesis) of heterocyclic dichalcogenolates C₃X₅^2? (X = Se: dsis; X = S/Se: C₃S_xSe_y^2?) is outlined. The 1,2-dichalcogenolate compounds were isolated and characterized as dibenzoyl derivatives. Bis- or tris-chelates of general type A_m[M(C₃X₅)_n] (with A = Bu₄N⁺, Ph₄As⁺; M = Zn^II, Pt^II, Pd^II, Ni^III, Cu^III, Au^III, In^III; X = Se, S/Se; m = 1, 2, 3; n = 2, 3, respectively) are available directly from methanolic solutions of the dibenzoylates after hydrolytic cleavage of the latter with sodium methanolate. In addition bis-chelates Bu₄N[Ni(C₃X₅)₂] (X = Se, S/Se) have been characterized by cyclovoltammetry and epr spectroscopy and compared with the corresponding all-sulfur ligand compound Bu₄N[Ni(dmit)₂] (X = S). Arguments are given for the fact that the allselenium ligand dsis (X = Se) yields the Cu^III or Ni^III chelate at once whereas with dmit using identical conditions the metal(II) compounds are formed.     

Photooxidation of Transition Metal Complexes of 1,3-Dithiole-2-thione-4,5-dithiolate (dmit) and 1,2-Dithiole-3-thione-4,5-dithiolate (dmt)

Metall(II) bis-chelates of 1,3-dithiole-2-thione-4,5-dithiolate (dmit) and 1,2-dithiole-3-thione-4,5-dithiolate (dmt) undergo in CHCl₃/CH₃CN (ratio 1:24) photooxidation to the metal(III) bis-chelates when irradiated at 313 nm. No side reactions were observed. There is no correlation between the quantum yields of photooxidation and the electrochemical halve-wave potentials. This holds also in comparison to maleonitriledithiolato chelates.     

Zur Koordinationschemie des 1,3-Dithiol-2-selon-4,5-diselenolats (dsise) und des 1,3-Dithiol-2-selon-4,5-dithiolats (dmise). Kristall- und Molekülstruktur des Tetrabutylammonium-bis-(1,3-dithiol-2-selon-4,5-diselenolato)nickelat(II) und -(III), [(n-C4H9)4N]2[Ni(dsise)2] und (n-C4H9)4N[Ni(dsise)2]

Coordination Chemistry of 1,3-Dithiole-2-selone-4,5-diselenolate (dsise) and 1,3-Dithiole-2-selone-4,5-dithiolate (dmise). Crystal and Molecular Structure of Tetrabutylammonium bis(1,3-dithiole-2-selone-4,5-diselenolato)nickelate(II) and -(III), [(n-C₄H₉)₄N]₂[Ni(dsise)₂ and (n-C₄H₉)₄[Ni(dsise)₂] Syntheses and properties of metal(II) and metal(III) bis-chelates of 1,3-dithiole-2-selone-4,5-diselenolate (dsise), of the general type (Bu₄N)_n)M(dsise)₂] (n =2 : M = Zn, Cd, Hg, Cu, Ni, Pd; n = 1: M = Ni, Au) are reported and compared with chelates of the isologue 1,3-dichalcogenole-2-chalcogenoe-4,5-dichalcogenolate (i. r., ¹³C-n. m. r., e. p. r., cyclovoltammetric data). The unexpected rearrangement during the syntheses of dsise and 1,3-dithiole-2-selone-4,5-diselenolate (dmise) is characterized by ab-initio SCF calculations. The x-ray structures of (Bu₄N)₂[Ni(dsise)₂] (space group P2₁/c, a = 8.5556(13) Å, b = 15.0009(12) Å, c = 19.696(3) Å, β = 96.018(7)°, V = 2513.9(5) ų, Z = 2) and Bu₄N[Ni(dsise)₂] (space group C2/c, a = 25.133(6) Å, b = 9.828(4) Å, c = 18.104(7) Å, β = 132.81(1)°, V = 3281(2) ų, Z = 4) are given.     

Extensively Conjugated Dianionic Tetrathiooxalate-Bridged Copper(II) Complexes for Synthetic Metals

Using a unique three-solvent biphasic method, we have prepared and characterized three new fully conjugated, chalcogen-rich, bridged copper(II) complexes for the preparation of molecular conductors and magnetic materials, having the general formula (Bu(4)N)(2){tto[Cu(L)](2)} (tto = C(2)S(4)(2)(-) = tetrathiooxalato; L = mnt = C(4)N(2)S(2)(2)(-) = 1,2-dicyanoethene-1,2-dithiolato for complex 2, dsit = C(3)Se(2)S(3)(2)(-) = 2-thioxo-1,3-dithiole-4,5-diselenolato for complex 3, dmid = C(3)OS(4)(2)(-) = 2-oxo-1,3-dithiole-4,5-dithiolato for complex 4a). The single-crystal X-ray structures of 2 and 3 have been determined: 2, (Bu(4)N)(2){tto[Cu(mnt)](2)}, monoclinic, space group C2/m, a = 19.549(4) ?, b = 13.519(3) ?, c = 10.162(2) ?, beta = 90.33(1) degrees, Z = 2; 3, (Bu(4)N)(2){tto[Cu(dsit)](2)}, monoclinic, space group P2(1)/c, a = 9.903(1) ?, b = 15.589(1) ?, c = 18.218(1) ?, beta = 90.40(1) degrees, Z = 2. Complex 2 displays perfect planarity, while 3 shows a slight tetrahedral distortion at the metal centers, resulting in a dihedral angle of 24.86(3) degrees. Cyclic voltammetry of (Bu(4)N)(2){tto[Cu(mnt)](2)} (2), (Bu(4)N)(2){tto[Cu(dsit)](2)} (3), and (Bu(4)N)(2){tto[Cu(dmid)](2)} (4a) shows each complex to exhibit two reversible redox processes which can be attributed to {tto[Cu(L)](2)}(2)(-) right arrow over left arrow tto[Cu(L)](2)}(-) and {tto[Cu(L)](2)}(1)(-) right arrow over left arrow {tto[Cu(L)](2)}(0) couples. The structural and electronic properties of 2, 3, and 4a will be compared to those of the recently communicated analogous complex (Bu(4)N)(2){tto[Cu(dmit)](2)} (1).     

ERP-Untersuchungen an Oxovanadium(IV)-Bis-Komplexen mit 1,2-Dithioliganden

EPR Studies on Oxovanadium(IV) Bis-Complexes of 1,2-Dithio Ligands EPR investigations on oxovanadium(IV) bis-complexes containing the ligands 1,3-dithiol-2-thione-4,5-dithiolate, dmit^2?, 1,2-dithiol-3-thione-4,5-dithiolate, dmt^2?, and 1,2-dithiooxalate are reported. The parameters of the spin-Hamiltonian are used to characterize the bonding properties, and are compared with those obtained for the corresponding VOS₄ chelates containing four-membered chelate rings. According to this a successful characterization of VOS₄ type mixed-ligand complexes should be possible.     

Synthese und Charakterisierung von Metallocen-Chelaten heterocyclischer 1,2-Diselenolate

Synthesis and Characterization of Metallocene Chelates of Heterocyclic 1,2-Diselenolates Synthesis and properties of metallocen diselenolates Cp₂^RML (Cp^R = η⁵-C₅H₄CH₃ (Cp′); η⁵-C₅(CH₃)₄ C₂H₅ (Cp^o)) of titanium(IV) and vanadium(IV) with L = dsit (1,3-dithiole-2-thione-4,5-diselenolate), dsise (1,3-dithiole-2-selone-4,5-diselenolate) dsitse (1,3-thiaselenole-2-selone-4,5-diselenolate) and dsis (1,3-diselenole-2-selone-4,5-diselenolate) are described. The structures of these compounds in solution are discussed using ¹H, ¹³C, ⁷⁷Se NMR and EPR data. Their voltammetric behaviour is investigated in dichloromethane. The activation parameters of the chelate ring inversion of the titanocene diselenolates (Cp₂^RTiL) and the x-ray structures of Cp₂′Ti(dsit), Cp₂^oTi(dsit); Cp₂^oTi(dsise) (2 modifications) and Cp₂^oTi(dsis) are reported.     

[AuII([12]anS4)]2+ – X‐ und Q‐Band‐EPR‐spektroskopischer Nachweis einer neuen monomeren Gold(II)‐Verbindung

[Au^II([12]anS₄)]²⁺ – X‐ and Q‐Band EPR Evidence of a New Monomeric Gold(II) Compound The reaction of [Au^IIICl₄]^– with the thiacrown ether [12]aneS₄ leads to an instable [Au^II([12]anS₄)]²⁺ complex (5d⁹, S = 1/2) which was characterized by X‐ and Q‐ band EPR. The spin Hamiltonian parameters g , A ^Au and P ^Au were derived using a program package allowing an exact diagonalisation of the spin‐Hamiltonian‐Matrix. The EPR parameters suggest the coordination of only one thiacrown ether ligand in the new Au^II complex.