| 1. |
- Bredyuk, O.A., et al.
(författare)
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Three-Dimensional Polymeric Thallium(I) Morpholinedithiocarbamate [Tl2{S2CN(CH2)4O}2]n and Its Capability of Binding Gold(III) from Solutions : Chemisorption Synthesis of a Heteronuclear Gold(III)–Thallium(III) Complex of the Ionic Type, ([Au{S2CN(CH2)4O}2][TlCl4])n, the Role of Secondary Interactions Tl…O, Tl…S, and Au…S in the Supramolecular Self-Organization, 13C MAS NMR, and Thermal Behavior
- 2017
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Ingår i: Russian journal of coordination chemistry. - : Maik Nauka Publishing. - 1070-3284 .- 1608-3318. ; 43:10, s. 638-651
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Tidskriftsartikel (refereegranskat)abstract
- Crystalline polymeric thallium(I) morpholinedithiocarbamate [Tl2{S2CN(CH2)4O}2]n (I) and the heteronuclear ion–polymeric gold(III)–thalium(III) complex ([Au{S2CN(CH2)4O}2][TlCl4])n (II) are preparatively isolated and characterized by X-ray diffraction analysis and 13C MAS NMR spectroscopy. According to the X-ray diffraction data, the main structural units of compounds I and II (CIF files CCDC 1548079 and 1548080) are presented by the binuclear centrosymmetric molecule [Tl2{S2CN(CH2)4O}2], noncentrosymmetric complex cation [Au{S2CN(CH2)4O{2]+, and isomeric complex anions [TlCl4]–. The formation of the three-dimensional polymeric structure (coordination number of Tl is 7), which is not characteristic of thallium(I) dithiocarbamates, is a consequence of the participation of the secondary Tl…O and Tl…S bonds of two types in the supramolecular self-organization of compound I. Nonequivalent secondary interactions of the first type join the binuclear molecules [Tl2{S2CN(CH2)4O}2] into polymer layers, which, in turn, form the three-dimensional polymeric framework due to the secondary bonds Tl…S. The revealed ability of freshly precipitated compound I to the chemisorption of gold(III) from solutions (2 M HCl) makes it possible to obtain heteronuclear supramolecular complex II as an individual form of binding. In the structure of the latter, the pairs of stronger secondary Au…S bonds join the gold(III) cations into dimers [Au2{S2CN(CH2)4O}4]2+ of the angular structure, the structural ordering of which is achieved in the cationcationic polymeric chain ([Au2{S2CN(CH2)4O}4]2+)n of the helical type involving the pairs of less strong Au…S bonds between the adjacent binuclear units. The distorted tetrahedral anions [TlCl4]– are localized between the polymeric chains. The study of the thermal behavior of compounds I and II by simultaneous thermal analysis makes it possible to establish the character of thermal transformations of the substances and to identify Tl2S (I), TlCl, and elemental gold (II) as thermolysis products
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| 2. |
- Gowda, Vasantha, et al.
(författare)
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Structural insights into the polymorphism of bismuth(III) di-n-butyldithiocarbamate by X-ray diffraction, solid-state (13C/15N) CP-MAS NMR and DFT calculations
- 2017
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Ingår i: Polyhedron. - : Elsevier. - 0277-5387 .- 1873-3719. ; 129, s. 123-132
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Tidskriftsartikel (refereegranskat)abstract
- Two crystalline polymorphs of a binuclear tris(di-n-butyldithiocarbamato)bismuth(III) complex, I and II, with an empirical formula of [Bi{S2CN(n-C4H9)2}3] were synthesised and characterised by X-ray diffraction (XRD), solid-state NMR and density functional theory (DFT) calculations. At the supramolecular level, these mononuclear molecular units interact in pairs via secondary Bi⋯S bonds, yielding binuclear formations of [Bi2{S2CN(n-C4H9)2}6]. The polymorph I () contains two isomeric non-centrosymmetric binuclear molecules of [Bi2{S2CN(n-C4H9)2}6], which are related to each other as conformers, therefore having four structurally inequivalent bismuth atoms and twelve inequivalent dithiocarbamate ligands. In contrast, the structurally simpler polymorph II (P21/n) exists as a single molecular form of the corresponding centrosymmetric binuclear formation, comprising two structurally equivalent bismuth atoms and three structurally different dithiocarbamate groups. The polymorphs I and II were found to be interconvertible by altering the solvent system during the recrystallisation process. Sun et al. (2012) has reported a crystalline form of the title compound which resembles, but is not identical with, polymorph II. Experimental solid-state 13C and 15N cross-polarisation (CP) magic-angle-spinning (MAS) NMR spectra of both polymorphs I and II were in accord with the direct structural data on these complexes. Assignments of the resonance lines in the solid-state 13C and 15N NMR spectra were assisted by chemical shift calculations of the crystals using periodic DFT.
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| 3. |
- Ivanov, Alexander V., et al.
(författare)
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A comparative study of the structural organization of nickel(II) and copper(II) complexes with dialkyl-substituted and cyclic dithiocarbamate ligands by X-ray single-crystal diffraction, EPR, and CP/MAS C-13 and N-15 NMR
- 2002
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Ingår i: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 47:3, s. 410-422
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Tidskriftsartikel (refereegranskat)abstract
- X-ray single-crystal diffraction, EPR, and CP/MAS C-13 and N-15 NMR were used for studying the structures and spectral properties of nickel(II) and copper(II) dithiocarbamate complexes [M(S2CNR2)(2)] (R = CH3, C2H5, C3H7, i-C3H7 or R-2 = (CH2)(5), (CH2)(6), (CH2)(4)O). The [CUS4] chromophores in the lattice of nickel(II) complexes have, predominantly, a square-planar structure. The chromophore geometry is somewhat distorted only in bis(morpholinedithiocarbamato)copper(II). Differences in the N-15 NMR isotropic chemical shifts of dialkyldithiocarbamate ligands were interpreted in terms of a unified conceptual approach based on the concept of joint manifestation of the mesomeric effect of dithiocarbamate groups and the inductive effect of alkyl substituents. Experimental NMR (C-13, N-15) signals were assigned to the structural positions of atoms in allowed molecular structures. Refined structural data on [Ni{S2CN(C3H7)(2)}(2)] point to the occurrence of two types of structurally nonequivalent complex molecules; the [Ni(S2CN(CH2)6)2] complex is characterized by the intramolecular nonequivalence of dithiocarbamate ligands.
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| 4. |
- Ivanov, Alexander V., et al.
(författare)
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A comparative study of the structural organization of zinc complexes with dialkyl-substituted and cyclic dithiocarbamate ligands : synthesis, single-crystal X-ray diffraction, and CP/MAS C-13 and N-15 NMR
- 2003
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Ingår i: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 48:1, s. 45-54
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Tidskriftsartikel (refereegranskat)abstract
- The structures and spectral properties of eight zinc(II) dithiocarbamate complexes [Zn-2(S2CNR2)(4)] (R = CH3, C2H5, C3H7, C3H7, C4H9; or R-2 = (CH2)(5), (CH2)(6), (CH2)(4)O) have been studied by single-crystal X-ray diffraction and CP/MAS C-13 and N-15 NMR. The experimental C-13 and N-15 NMR signals have been assigned to the positions of the corresponding atoms in the ligands with different structural functions (terminal or bridging). Differences in the N-15 NMR isotropic chemical shifts of dialkyldithiocarbamate ligands have been interpreted based on the concept of joint manifestation of the mesometic effect of dithiocarbamate groups and the inductive effect of alkyl substituents. The zinc dibutyl-, pentamethylene-, and morpholinedithiocarbamate complexes have been prepared and comprehensively characterized. The binuclear complex [Zn-2{S2CN(C4H9)(2)}(4)] appears to be the second example of a noncentrosymmetiic molecule of zinc dithiocarbamate. Another structural feature of the dimer is the fact that the eight-membered [Zn2S4C2] metallacycle is stabilized in the boat rather than in the chair conformation.
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| 5. |
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| 6. |
- Ivanov, Alexander V., et al.
(författare)
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Adduct formation of the zinc morpholinedithiocarbamate complex with morpholine as studied by CP/MAS 15N NMR and single-crystal X-ray diffraction
- 2004
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Ingår i: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 49:12, s. 1863-1870
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Tidskriftsartikel (refereegranskat)abstract
- The adduct of the zinc morpholineditiohcarbamate complex with morpholine [Zn(Mf)(MfDtc)2] and its solvated form [Zn(Mf)(MfDtc) 2]·Mf were studied by CP/MAS 15N NMR and single-crystal X-ray diffraction. These complexes are molecular, and the dithiocarbamate ligands therein are structurally nonequivalent. Solvation of the adduct aggravates this nonequivalence. The molecular and crystal structure of [Zn(Mf)(MfDtc)2]·Mf was determined by X-ray crystallography. The crystal structure of this compound has a system of ordered channels accommodating the outer-sphere morpholine molecules of solvation, which points to the formation of clathrate structures. The zinc coordination polyhedron [ZnS4N] is a somewhat distorted square pyramid with the four sulfur atoms at the base and the nitrogen atom at the apex. The square-pyramidal (SP) (97%) and trigonal-bipyramidal (TBP) (3%) contributions to the geometry of the zinc polyhedron were calculated. The 15N NMR signals were assigned to the structural positions of the nitrogen atoms in the molecular structure determined
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| 7. |
- Ivanov, Alexander V., et al.
(författare)
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Adducts of Diethyldithiocarbamate Complexes of Zinc(II) and Copper(II) with Piperidine [M(Pip)(Edtc)2] and Their Solvated Forms [M(Pip)(Edtc)2] · L (L = C6H6, C5H5N, C4H9NO): Synthesis, EPR and Solid-State (13C, 15N) CP/MAS NMR Studies
- 2001
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Ingår i: Russian journal of coordination chemistry. - 1070-3284 .- 1608-3318. ; 27:3, s. 158-166
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Tidskriftsartikel (refereegranskat)abstract
- Crystal adducts of diethyldithiocarbamate complexes of zinc(II) and copper(II) with piperidine (Pip) were synthesized, and their solvated forms with the outer-sphere molecules of benzene, pyridine (Py), and morpholine (Mf) were obtained. Adducts with composition [M(Pip)(Edtc)2] · L (L = Py, Mf) were shown to be able, in principle, to give solvated isomers [M(L)(Edtc)2] · Pip with the Pip molecule arranged in the outer sphere. The composition, structure, and properties of the obtained adducts were studied by EPR, high-resolution solid-state 13C, 15N NMR spectroscopy. Solvation of all three adducts with Pip, Mf, and Py was found to result in a substantial increase in the contribution of the trigonal-bipyramidal component to the geometry of a copper coordination pentahedron. In addition, for adducts with Mf and Py, a structural unification of two isomeric forms was observed at the molecular level to yield a qualitatively new (rather than intermediate) state. It was shown that in all solvated forms of the copper(II) adducts, the metal polyhedron is mainly a trigonal bipyramid, while the square-pyramidal contribution is insignificant. Results of (13C, 15N) NMR studies revealed a structural inequivalence of the Edtc-ligands in the zinc adducts under investigation.
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| 8. |
- Ivanov, Alexander V., et al.
(författare)
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Adducts of zinc and copper(II) dialkyldithiocarbamate complexes with dialkylamines: Synthesis, EPR, and 13C and 15N CP/MAS NMR
- 2007
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Ingår i: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 52:5, s. 691-697
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Tidskriftsartikel (refereegranskat)abstract
- Crystalline adducts of zinc and copper(II) dithiocarbamate (Dtc) complexes with dialkylamines [M(NHR′2)(S2CNR2)2] (M = Zn, 63Cu, 65Cu; R = CH3, C2H5, or R2 = (CH2)4O; R′ = C2H5, C3H7) have been preparatively isolated. The structures and spectral properties of the adducts have been studied by EPR and 13C and 15N MAS NMR. Chemisorption of bases on powders of dinuclear dithiocarbamates leads to their dissociation into monomeric adducts. Computer simulation demonstrates that the experimental EPR spectra of isotope-substituted copper(II) adducts have an individual character. The geometry of the copper polyhedra is intermediate between a trigonal bipyramid (TBP) and a tetragonal pyramid (TP). The TBP and TP contributions have been quantified based on EPR data. 13C and 15N MAS NMR data show that the Dtc ligands incorporated into the zinc adduct molecule are structurally nonequivalent. The dependence of the isotropic 15N chemical shifts of the Dtc groups on the alkyl substituents at the nitrogen atom is interpreted based on the concept of joint manifestation of the (+)inductive effect of the alkyl substituents and the mesomeric effect of the Dtc groups.
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| 9. |
- Ivanov, Alexander V., et al.
(författare)
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Adducts of zinc and copper(II) dialkyldithiocarbamate complexes with hexamethyleneimine: Synthesis, EPR, and CP/MAS 13C and 15N NMR
- 2004
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Ingår i: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 49:1, s. 95-101
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Tidskriftsartikel (refereegranskat)abstract
- Powders of the zinc and copper(II) dimethyl- (MDtc), diethyl- (EDtc), and morpholinedilhiocarbamate (MfDtc) complexes quantitatively absorb hexamethyleneimine (Hmi) to produce the adducts [M{NH(CH2) 6}(S2CNR2)2] (M = Zn, Cu; R = CH3, C2H5; R2 = (CH 2)4O). The heterogeneous reaction of adduct formation is accompanied by dissociation of the binuclear molecules [M2(DtC) 4] of the initial dithiocarbamate complexes. Computer-aided simulation of EPR spectra for the copper(II) adducts shows that they are individual. The coordination polyhedron of copper in these compounds is intermediate between a trigonal bipyramid (TBP) and a square pyramid (SP). Based on EPR data, the TBP contribution is quantitatively estimated. 13C and 15N NMR shows that the MDtc and EDtc ligands in the adducts are structurally nonequivalent, whereas the MfDtc ligands are structurally equivalent. The 15N isotropic chemical shifts of the dithiocarbamate groups depend on alkyl substituents at the nitrogen atom.
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| 10. |
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